mmm Is it ( Unauthorized Military Presence )? Maybe you need to tweak your setup a bit? I use active armor tanking though.. im sure there is something similar with active resist modules for shield tanks as well. I do confess i know nothing about shield tanks but i do know that Ravens are really good mission boats.. i have a friend running lvl4s with one with out Logistics support. ?(

There is also warp stabs, or maybe sensor dampeners? (i dont know much about the dampeners though)

Wish i could help here.. :S