diff -urN libvirt-0.6.2/src/qemu_conf.c libvirt-0.6.2-bigargv//src/qemu_conf.c
--- libvirt-0.6.2/src/qemu_conf.c	2009-04-02 05:50:10.000000000 -0400
+++ libvirt-0.6.2-bigargv//src/qemu_conf.c	2009-05-13 15:03:46.000000000 -0400
@@ -431,7 +431,7 @@
         return -1;
 
     char *help = NULL;
-    enum { MAX_HELP_OUTPUT_SIZE = 8192 };
+    enum { MAX_HELP_OUTPUT_SIZE = 16384 };
     int len = virFileReadLimFD(newstdout, MAX_HELP_OUTPUT_SIZE, &help);
     if (len < 0)
         goto cleanup2;
