--- graphviz-2.18/tclpkg/gv/gv_php_init.c.orig	2007-11-16 21:20:49.000000000 +0100
+++ graphviz-2.18/tclpkg/gv/gv_php_init.c	2008-05-31 21:48:43.663241115 +0200
@@ -22,11 +22,13 @@
 
 static size_t gv_string_writer (GVJ_t *job, const char *s, size_t len)
 {
+    TSRMLS_FETCH();
     return PHPWRITE(s, len);
 }
 
 static size_t gv_channel_writer (GVJ_t *job, const char *s, size_t len)
 {
+    TSRMLS_FETCH();
     return PHPWRITE(s, len);
 }