Problem with disappearing Gradients

[jlorenz]

Never had this problem before but I've got some tables (with a single td) that I changed to Microsoft.Gradient and it goes away (background goes transparent) on mouse over in the parent table column. Any ideas??

see at http://www.aircraftjournal.com/index.html

css used:

#right_column_table {
border: 2px solid #898888;
filter:progid:DXImageTransform.Microsoft.Gradient
(GradientType=0,StartColorStr='#E5E5E5',EndColorStr='#B1B0B0');
}

thanks