--- a/config.h.in
+++ b/config.h.in
@@ -879,6 +879,13 @@
    #define below would cause a syntax error. */
 #undef _UINT64_T
 
+/* Kludgey fix for Gentoo bug #492710, caused by improper use of the Tcl API.
+ * Upstream should be using Tcl_SetObjResult, Tcl_GetObjResult, and/or
+ * Tcl_GetStringResult. This is the simplest way for us to fix it, and should
+ * be removed as soon as GST uses the Tcl interface correctly.
+ */
+#define USE_INTERP_RESULT 1
+
 /* Define for Solaris 2.5.1 so the uint8_t typedef from <sys/synch.h>,
    <pthread.h>, or <semaphore.h> is not used. If the typedef were allowed, the
    #define below would cause a syntax error. */