Using an image as a bg color was never intended. Instead it was fixed so bgcolor can now support #rrggbbaa. If you want it to work how it was before, for aa just use the first two characters of the image you were trying to use in the first place.
HTML Code:
<body bgcolor =#fff1ffsu><font color=white>have ideas for Xmas hats? pm me them :s
I don't condone the use of "su" as an alpha value though! That's not proper hex code... I suggest: #fff1ffdd