I was in a mission, fought an NPC trader (can't remember if it was a Rookie Trader or Novice Nanoshifter -- mission was around QL 60). Anyway, near the end of the fight, I of course get Ransack Skills (Major) or something similar cast on me... Being low on nano energy, I sat down and tried to use a nano recharger. D'oh! Time&Space skill too low. So I cast T&S Expertise on myself to raise it enough to be able to use the recharger. D'oh! T&S still too low. Sigh. So I decided to wait the 3 minutes necessary for the Ransack to end. Once it was gone, I tried to use the recharger again. D'oh! T&S still too low. I pressed 'U' to examine my skills, only to discover that all my my nano skills were fine (normal), except for the T&S skill (much lower than normal -- not colored red though)! Logging off and back on corrected the problem.
Not sure what happened since this is the first time I saw this occur, but I am guessing that if you cast an expertise while ransacked and then the ransack wears off, the corresponding skill doesn't reset back to normal.