uClibc does not have backtrace support right now. Disable it for now.

--- openjdk-6.orig/jdk/src/solaris/native/sun/xawt/XToolkit.c	2011-02-28 17:06:50.000000000 +0100
+++ openjdk-6/jdk/src/solaris/native/sun/xawt/XToolkit.c	2011-08-08 10:45:01.445330729 +0200
@@ -27,9 +27,6 @@
 #include <X11/Xutil.h>
 #include <X11/Xos.h>
 #include <X11/Xatom.h>
-#ifdef __linux__
-#include <execinfo.h>
-#endif
 
 #include <jvm.h>
 #include <jni.h>
@@ -689,7 +686,7 @@
     return ret;
 }
 
-#ifdef __linux__
+#if 0
 void print_stack(void)
 {
   void *array[10];