diff --git a/config.h.in b/config.h.in
index 5647ef6..191cef8 100644
--- a/config.h.in
+++ b/config.h.in
@@ -87,6 +87,9 @@
 /* Define to 1 if you have the <sys/param.h> header file. */
 #undef HAVE_SYS_PARAM_H
 
+/* Define to 1 if you have the <sys/socket.h> header file. */
+#undef HAVE_SYS_SOCKET_H
+
 /* Define to 1 if you have the <sys/statfs.h> header file. */
 #undef HAVE_SYS_STATFS_H
 
diff --git a/configure b/configure
index 411592d..0d31863 100755
--- a/configure
+++ b/configure
@@ -5585,7 +5585,7 @@ fi
 
 done
 
-for ac_header in sys/ustat.h sys/sysmacros.h sys/syslog.h
+for ac_header in sys/ustat.h sys/sysmacros.h sys/syslog.h sys/socket.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
 ac_fn_c_check_header_mongrel "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default"
diff --git a/configure.ac b/configure.ac
index 66afe85..eb73eae 100644
--- a/configure.ac
+++ b/configure.ac
@@ -63,7 +63,7 @@ AC_CHECK_HEADERS(sys/mount.h,,,
 #include <sys/param.h>
 #endif
 ]])
-AC_CHECK_HEADERS(sys/ustat.h sys/sysmacros.h sys/syslog.h)
+AC_CHECK_HEADERS(sys/ustat.h sys/sysmacros.h sys/syslog.h sys/socket.h)
 AC_CHECK_HEADERS(unistd.h syslog.h langinfo.h sys/statfs.h)
 AC_CHECK_HEADERS(signum.h bits/signum.h, break )
 AC_CHECK_HEADERS(stdarg.h varargs.h, break )
diff --git a/src/core/unixfsservices.cpp b/src/core/unixfsservices.cpp
index eae67e0..ac7ed07 100644
--- a/src/core/unixfsservices.cpp
+++ b/src/core/unixfsservices.cpp
@@ -72,9 +72,13 @@
 #endif
 #include <sys/utsname.h>
 #include <pwd.h>
-#include <sys/socket.h>
-#include <netdb.h>
-#include <netinet/in.h>
+
+#if HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+# include <netdb.h>
+# include <netinet/in.h>
+#endif
+
 #include <grp.h>
 #include <fcntl.h>
 #include <errno.h>
@@ -365,7 +369,11 @@ void cUnixFSServices::Stat( const TSTRING& strNameC, cFSStatArgs& stat) const th
     stat.size       = statbuf.st_size;
     stat.uid        = statbuf.st_uid;
     stat.blksize    = statbuf.st_blksize;
+#ifndef __DJGPP__
     stat.blocks     = statbuf.st_blocks;
+#else
+    stat.blocks     = 0;
+#endif
 
     // set the file type
     if(S_ISREG(statbuf.st_mode))    stat.mFileType = cFSStatArgs::TY_FILE;
@@ -374,7 +382,9 @@ void cUnixFSServices::Stat( const TSTRING& strNameC, cFSStatArgs& stat) const th
     else if(S_ISBLK(statbuf.st_mode))   stat.mFileType = cFSStatArgs::TY_BLOCKDEV;
     else if(S_ISCHR(statbuf.st_mode))   stat.mFileType = cFSStatArgs::TY_CHARDEV;
     else if(S_ISFIFO(statbuf.st_mode))  stat.mFileType = cFSStatArgs::TY_FIFO;
+#ifdef S_ISSOCK
     else if(S_ISSOCK(statbuf.st_mode))  stat.mFileType = cFSStatArgs::TY_SOCK;
+#endif
 #ifdef S_IFDOOR
     else if(S_ISDOOR(statbuf.st_mode))  stat.mFileType = cFSStatArgs::TY_DOOR;
 #endif
@@ -399,7 +409,7 @@ void cUnixFSServices::GetMachineNameFullyQualified( TSTRING& strName ) const
     char buf[256];
     if (gethostname(buf, 256) != 0)
     {
-#if defined(SOLARIS_NO_GETHOSTBYNAME) || defined(_SORTIX_SOURCE)
+#if defined(SOLARIS_NO_GETHOSTBYNAME) || defined(_SORTIX_SOURCE) || defined(__DJGPP__)
         strName = buf;
         return;
 #else
@@ -454,7 +464,7 @@ bool cUnixFSServices::GetIPAddress( uint32& uiIPAddress )
     bool    fGotAddress = false;    
     cDebug  d( _T("cUnixFSServices::GetIPAddress") );
 
-#ifndef _SORTIX_SOURCE
+#if !defined(_SORTIX_SOURCE) && !defined(__DJGPP__)
     struct utsname utsnameBuf;    
     if( EFAULT != uname( &utsnameBuf) )
     {
@@ -557,6 +567,10 @@ bool cUnixFSServices::GetGroupForFile( const TSTRING& tstrFilename, TSTRING& tst
     return( fSuccess );
 }
 
+#ifndef S_ISVTX // DOS/DJGPP doesn't have this
+# define S_ISVTX 0
+#endif
+
 ////////////////////////////////////////////////////////////////////////
 // Function name    : cUnixFSServices::ConvertModeToString
 // Description      : takes a TSTRING and fills it with an "ls -l" representation
diff --git a/src/cryptlib/misc.h b/src/cryptlib/misc.h
index 467a7a7..95a4711 100644
--- a/src/cryptlib/misc.h
+++ b/src/cryptlib/misc.h
@@ -9,7 +9,7 @@
  #include <string.h>
 #endif
 
-#ifdef __MINT__ // has memory.h, but memset defined in string.h anyway.
+#if defined(__MINT__) || defined(__MSDOS__) // has memory.h, but memset defined in string.h anyway.
  #include <string.h>
 #endif
 
diff --git a/src/tripwire/mailmessage.h b/src/tripwire/mailmessage.h
index 866d389..e138258 100644
--- a/src/tripwire/mailmessage.h
+++ b/src/tripwire/mailmessage.h
@@ -37,9 +37,11 @@
 #endif
 
 
-#if IS_UNIX
-#include <sys/socket.h>
-#define SOCKET int
+#if IS_UNIX 
+# if HAVE_SYS_SOCKET_H
+#  include <sys/socket.h>
+# endif
+# define SOCKET int
 #endif
 
 
diff --git a/src/tripwire/smtpmailmessage.cpp b/src/tripwire/smtpmailmessage.cpp
index ea01129..f57c39a 100644
--- a/src/tripwire/smtpmailmessage.cpp
+++ b/src/tripwire/smtpmailmessage.cpp
@@ -46,12 +46,14 @@
 
 //All the spleck that it takes to run sockets in Unix...
 #include <stdio.h>
-#include <sys/socket.h>
+#if HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+# include <netdb.h>
+# include <netinet/in.h>
+# include <arpa/inet.h>
+#endif
 #include <sys/types.h>
 #include <sys/time.h>
-#include <netdb.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
 #include <sys/utsname.h>
 
 #ifdef _SORTIX_SOURCE
@@ -191,12 +193,16 @@ long cSMTPMailMessage::GetServerAddress()
 
     if (bIsNumeric)
     {
+#ifndef HAVE_SYS_SOCKET_H
+        return 0;
+#else
         // convert the numberic address to a long
         return mPfnInetAddr(sNarrowString.c_str());
+#endif
     }
     else
     {
-#ifdef _SORTIX_SOURCE
+#if defined(_SORTIX_SOURCE) || !defined(HAVE_SYS_SOCKET_H)
         return INADDR_NONE;
 #else
         // do a DNS lookup of the hostname and get the long
@@ -216,6 +222,9 @@ long cSMTPMailMessage::GetServerAddress()
 //
 bool cSMTPMailMessage::OpenConnection()
 {
+#ifndef HAVE_SYS_SOCKET_H
+    return false;
+#else
     // Initialize the socket structure
     sockaddr_in sockAddrIn;
     memset(&sockAddrIn, 0, sizeof(sockaddr));
@@ -262,6 +271,7 @@ bool cSMTPMailMessage::OpenConnection()
     }
 
     return true;
+#endif
 }
 
 
@@ -485,6 +495,9 @@ bool cSMTPMailMessage::MailMessage()
 //
 bool cSMTPMailMessage::GetAcknowledgement()
 {
+#ifndef HAVE_SYS_SOCKET_H
+    return false;
+#else  
     cDebug d( "cSMTPMailMessage::GetAcknowledgement" );
 
     const int bufsize = 512;
@@ -547,17 +560,19 @@ bool cSMTPMailMessage::GetAcknowledgement()
         throw eMailSMTPServer(estr.str());
         return false;
     }
+#endif
 }
 
 void cSMTPMailMessage::SendString( const std::string& str )
 {
     cDebug d("util_SendString()");
-
+#if HAVE_SYS_SOCKET_H
     if( str.length() < 800 )
         d.TraceDebug( "Sending \"%s\"\n", str.c_str() );
     else
         d.TraceDebug( "Sending (truncated in this debug output)\"%s\"\n", std::string( str.c_str(), 800 ).c_str() );
     mPfnSend( mSocket, str.c_str(), str.length(), 0 );
+#endif
 }
 
 
diff --git a/src/tw/twinit.cpp b/src/tw/twinit.cpp
index 5b48b86..f21f9b1 100644
--- a/src/tw/twinit.cpp
+++ b/src/tw/twinit.cpp
@@ -284,7 +284,7 @@ void cTWInit::Init( const TSTRING& strArgv0 )
     mpData->et.SetChild( &mpData->er );
     errorQueue.SetChild( &mpData->et );
 
-#if IS_UNIX
+#if IS_UNIX && !defined(__DJGPP__)
     // ignore SIGPIPE
     tw_sigign(SIGPIPE); //TODO: somebody add comment here!