Cell death after electroporation - (Oct/28/2008 )

I electroporated E. coli DH5alpha with 2 microliters of ligation and I failed to recover any colony on selective medium the day after. The weird thing is that, despite no arcing during electroporation, after 1 hr of recovery in LB medium a sort of whitish jelly stuff, which I guess is coli DNA, was released in the medium.
Is it possible that failure to obtaine colonies was due to cell death? If yes, would it be due to ligase, salts or whatever? Is it compulsory to clean ligation prior to electroporation?

Controls, sir. Can you electroporate dilute plasmid DNA and recover cells? If not, then you have a problem with your electroporation protocol or equipment. If so, you have a problem with your ligations or (more likely) DNA preparation. Which is it?