Curiously, I run Ubuntu the same laptop with the same wireless card, and
I don't have that problem.
However, I'm debugged enough Linux "suspend" problems to understand how
this might be addressed.
Before you suspend, open "System: Administration: System Log", select
the "messages" log and scroll down to the bottom. Before and after
suspend, see if any errors or notices are generated there. You might see
a message about a networking/suspend problem, which would be a clue
about what to do next.
I could also look at it in person some time.
There is also an alternate way of suspending, described here:
http://blog.paulbetts.org/index.php/2007/02/11/fixing-software-suspend-hibernate-with-uswsusp-in-ubuntu-feisty-and-edgy/
Mark