First item in CR description is non-issue. The interfaces are not public API and are not bound by external consumption.
The cache upgrade issue is real, but the cache entries files was of cache version 602, which definitely were not produced with 6u32 (as I ran this version, I got cache entries version 603, which has no problems upgrading). It probably from JRE 1.5 or 1.6.0_02 at most.
The cause of the cache upgrade 602 failure was from the caching refactoring (CR 7163312), which also includes the cache version increment and the restructuring cache upgrade code.