- use svnversion in win32 build script

diff --git a/win32-cross-build.sh b/win32-cross-build.sh
index c5740de..c78f03a 100755
--- a/win32-cross-build.sh
+++ b/win32-cross-build.sh
@@ -1,8 +1,5 @@
 #!/bin/sh
-svn up
-STAT=$(svn status)
-test "x$STAT" == "x" || PLUS="+"
-REV=$(svn info | grep Revision | cut -d' ' -f2)$PLUS
+REV=$(svnversion)
 export CFLAGS="-I../../portaudio/include/ -I../../pthreads-w32-2-8-0-release/ -DPORTAUDIO -DREV='\"r$REV\"'"
 export LDFLAGS='-L../../pthreads-w32-2-8-0-release -L../../portaudio/lib/.libs'