This state of emergency is only meant to topple the top judges of supreme court of pakistan, specially cheif justice of pakistan justice iftikhar chaudry. The supreme court ruled against the goverment in one of the biggest corruptiuon cases of pakistan, arrests of innocent people by agencies etc.
“...it is clear from reading the emergency proclamation the main target is the judiciary which is accused of interfering in government policy...” -BBC News
http://news.bbc.co.uk/1/hi/world/south_asia/7076670.stm
The text of the decree makes that very clear. The pretext, the surrender of 48 soldiers, combined with the move to "protect" Butto's home may indicate far more serious problems coming to a head.