Java startup becomes slow due to temporary files

FULL PRODUCT VERSION :
1.6.0_12

ADDITIONAL OS VERSION INFORMATION :
Windows XP SP3

A DESCRIPTION OF THE PROBLEM :
When using Java on Windows XP, Java plugin stores JAR cache files in he Windows TEMP directory and don't delete these cache files.
If there are too much JAR cache files, Java startup becomes slower than before.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run applet on one machine so many times, and JAR cache files (ex. jar_cache###.tmp) are stored more than 100 MB.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
If no cache files in Windows TEMP directory, Java start up within 10 seconds.
ACTUAL -
With 236 MB cache files, Java start up for 45 seconds.
With 70MB cache files, Java start up for 20 seconds.

REPRODUCIBILITY :
This bug can be reproduced often.

CUSTOMER SUBMITTED WORKAROUND :
Delete these cache files.