As of now Cache.getCacheEntryFromIdxFiles() checks whether IP address of cached entry and currently requested entry are the same.

For the case of cached application this means performing DNS lookup that might be noticeable. 
Note that it is not easy to reproduce in dev enviromenmet as OS will cache these data for you
but for casual user this might have much noticeable impact. 
For local experiments you may clear DNS cache with |ipconfig /flushdns| on XP (Vista requires running same command as Admin). It will not show worst case scenario too
(as your nearby DNS server cache will be used) but at least this should cause network request
and they are relatively expensive.

This was introduced as part of fix for 6594007 but if applet does not try to perform network connections then it will be nice to avoid this check. See comments for desctiption of potential solution.