I have been trying to reproduce your error in our lab, but Update Manager didn't crash. Could you please run Update Manager in debug mode and send us the output to the address prodreg-help@sun.com?
Use the following command:
# updatemanager -debug 2>&1 >updatemanagerDebug.out
Please include the thread ID number 26587 on the subject and this
url at the end of the e-mail body:
http://forum.sun.com/thread.jspa?forumID=275&threadID=26587
Thanks.