PayPal As Forex Trading Tool?

Ever since I got my US $1.95 back from the PayPal verification fee, I’ve been wondering if I could use PayPal as a means to buy US Dollars and then sell (withdraw) them when its value appreciates.

I was billed US $1.95 in December of 2007 in my credit card at around P44.80 per US $1. PayPal credited the $1.95 to my account after verifying my credit card. The US Dollar then went as low as P39 before the value of the Philippine Peso corrected. As of this writing, a dollar is equivalent to around P43.80. That means if I added funds to my PayPal account when the dollar was just P39, and withdrew those funds now that a dollar is around P43.80, I would have earned P4.8 per dollar or 12% increase in value.

This has crossed my mind lots of times. And if only I had the excess cash, I might have done already. But before that I wanna know what you guys think of it. Can PayPal be used as a Forex trading tool?