I am unable to compile AWN in Ubuntu 13.04

[kenn]

I'm trying to compile AWN on Ubuntu 13.04 32 platform but I get following error

vala-utils.cc:358:6: error: no previous declaration for 'void awn::vala_array_destroy(gpointer, gint, GDestroyNotify)' [-Werror=missing-declarations]
cc1plus: some warnings being treated as errors
make[3]: *** [libawn_la-vala-utils.lo] Error 1

If I remove -Werror lines in configure.ac I still get error messages like

warning: comparison between signed and unsigned integer expressions

How can I smoothly compile it?