diff --git a/devel/ptlib/Makefile b/devel/ptlib/Makefile
index fa61300f1a3..0c255da626b 100644
--- a/devel/ptlib/Makefile
+++ b/devel/ptlib/Makefile
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.3 2010/03/27 14:32:23 ajacoutot Exp $
+# $OpenBSD: Makefile,v 1.4 2010/05/11 07:23:23 espie Exp $
 
 SHARED_ONLY=	Yes
 
@@ -33,6 +33,11 @@ BUILD_DEPENDS=	::devel/bison \
 LIB_DEPENDS=	lber,ldap,ldap_r::databases/openldap \
 		SDL::devel/sdl
 
+.include <bsd.own.mk>
+.if !${COMPILER_VERSION:L:Mgcc4}
+PATCH_LIST = patch-* gcc3-patch-*
+.endif
+
 CONFIGURE_STYLE=gnu
 CONFIGURE_ARGS=	${CONFIGURE_SHARED} \
 		--with-plugin-installdir=ptlib \
diff --git a/devel/ptlib/files/sound_sndio.cxx b/devel/ptlib/files/sound_sndio.cxx
index 851f18d6ebb..a581033e931 100644
--- a/devel/ptlib/files/sound_sndio.cxx
+++ b/devel/ptlib/files/sound_sndio.cxx
@@ -25,6 +25,11 @@
  * All Rights Reserved.
  *
  * $Log: sound_sndio.cxx,v $
+ * Revision 1.2  2010/05/11 07:23:23  espie
+ * make it compile on gcc4, by making the relevant patch dependent on
+ * compiler version.
+ * also removes lvalue cast, that's not ansi.
+ *
  * Revision 1.1.1.1  2010/03/23 21:10:17  ajacoutot
  * Import ptlib-2.6.5
  *
@@ -246,7 +251,7 @@ PBoolean PSoundChannelSNDIO::Write(const void * buf, PINDEX len)
       return FALSE;
     }
     len -= did;
-    (char *)buf += did;
+    buf = (char*)buf + did;
     tot += did;
   }
   lastWriteCount += tot;
@@ -270,7 +275,7 @@ PBoolean PSoundChannelSNDIO::Read(void * buf, PINDEX len)
       return FALSE;
     }
     len -= did;
-    (char *)buf += did;
+    buf = (char*)buf + did;
     tot += did;
   }
   lastReadCount += tot;
diff --git a/devel/ptlib/patches/patch-include_ptlib_safecoll_h b/devel/ptlib/patches/gcc3-patch-include_ptlib_safecoll_h
similarity index 96%
rename from devel/ptlib/patches/patch-include_ptlib_safecoll_h
rename to devel/ptlib/patches/gcc3-patch-include_ptlib_safecoll_h
index e860b4af1aa..ede06504418 100644
--- a/devel/ptlib/patches/patch-include_ptlib_safecoll_h
+++ b/devel/ptlib/patches/gcc3-patch-include_ptlib_safecoll_h
@@ -1,4 +1,4 @@
-$OpenBSD: patch-include_ptlib_safecoll_h,v 1.1.1.1 2010/03/23 21:10:17 ajacoutot Exp $
+$OpenBSD: gcc3-patch-include_ptlib_safecoll_h,v 1.1 2010/05/11 07:23:23 espie Exp $
 
 Make this build on gcc3.
 (reversed commit from upstream SVN)