FULL PRODUCT VERSION :
JRE 1.7.0_01

ADDITIONAL OS VERSION INFORMATION :
Replicated on Server 2008 R2 Standard but reported on others.

EXTRA RELEVANT SYSTEM CONFIGURATION :
Proxy server is Microsoft ISA 2006 atop W2k3

A DESCRIPTION OF THE PROBLEM :
After changing to Java 7, Web Start begins to prompt for proxy authentication every time we attempt to run our application via the jnlp link. Leaving the username and password empty and clicking OK allows web start to proceed.


REPRODUCIBILITY :
This bug can be reproduced always.