diff -Naur libdvdnav.orig/src/dvdnav.c libdvdnav/src/dvdnav.c
--- libdvdnav.orig/src/dvdnav.c	2009-03-13 18:28:22.000000000 -0700
+++ libdvdnav/src/dvdnav.c	2009-04-24 19:52:52.000000000 -0700
@@ -178,9 +178,9 @@
 #ifdef LOG_DEBUG
   fprintf(MSG_OUT, "libdvdnav: clearing dvdnav\n");
 #endif
+  pthread_mutex_unlock(&this->vm_lock);
   result = dvdnav_clear(this);
 
-  pthread_mutex_unlock(&this->vm_lock);
   return result;
 }