Can't show excerpt archive.php in Short URL Generator plugins

This is a great plugins, but i have problem when i use it

the excerpt function in the archive.php has been error, and can’t show excerpt posts in archive but show the full posts in archive, i’m very confused about it

when i’m deactivated this plugins the excerpt function in archive.php back to normal, i think the code on this plugins crash with the excerpt code on function.php

as you know, i used wordpress 3.1

can you help me about this problem, i think i can’t use another short url plugins because this plugins is so very good

Thanks