I had the same experience, and it was with Etrade also. I checked my purchasing power and it said I was able to purchase a non marginable stock without adding any more money. PPHM has been non marginable. I bought 3000 more shares @ 2.01. The next morning I got a margin call for the $6000.
I sold @ $2.03 and figured it was a glitch on E trades' part. Would have been nice if we PR'd a partner and the stock opened at $6.00....GLTA
I am not on margin now... but I have made a couple trades on margin with Fidelity and had five (5) days to deposit the funds to cover the trade.
This was after .... after the fact that I thought I could just run the shares on my margin account since I was approved for margin but it was sort of a blessing in disguise because I settled my margin account on Thursday (before black Monday). The following day (friday) I was pissed I settled my account for a smaller profit than if I waited till friday when the stock continued to rise above $5. Over the weekend I was more pissed because I thought it could have opened Monday or any day that week closer to $10 on a partnering deal and we all know the rest of the story. So yes... margin is rrrriiissskkkyyyy if you don't have plenty of money sitting around just in case.
This is why the hedge funds and big boys run the table over most of us.... they have the money to hedge their bets on the short side.... call options.... and many other ways. This is why I believe those 8M shares on the short side are with the big boys who will cover "much earlier" than anyone else and after they cover and the rest of the market starts to buy in... their shares on the long side are making more than enough to off set those short shares.... and they probably hold many call options as well.
I just wait for some news.... and with every stock and story... you learn a little more for your future trading. : )
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