The short col should be shorter like this:

Short	Long long long long	Long long long long
Short	Long long long long	Long long long long

But when adding a cell spanning both short and long cols (colspan=2 and width=20+40=60%) the widths of the first and second column gets scruwed up):

Short + Long long long		Long long long long
Short	Long long long long	Long long long long
Short	Long long long long	Long long long long