[TYPO3-Performance] dmc_highPerformance and wrong chars

[Vahan Amirbekyan]

folks,
I ran into strange for me issue.
I installed the dmc_highPerformance ext and all works fine but sometimes I 
see wrongs charactes in the FE as well as in the BE. For instance ">" char 
becomes a "?" char and a like. Somethins wrong with coding but where?
If I uninstall dmc_highPerformance all is back to normal.

thank you for any advice.