Custom expression fails in 1.3.1

Custom expression fails in 1.3.1


Custom expressions like the ones in jQMinMax fail with an error when
used in the selector. (jQMinMax is found here:
http://davecardwell.co.uk/javascript/jquery/plugins/jquery-minmax/)
All browsers fail with an error that 'filter is not a function' in the
line:
return filter( elem, i, match, array );
Is the old method of adding a new expression as a string instead of a
function not valid anymore or was this method wrong from the start?
Old method: $.expr[':']['expression'] = expr; // this works in 1.2.6,
but fails in 1.3.1
Simple fix: $.expr[':']['expression'] = function(a) { eval(expr); }
Maybe jQuery can check if the expression is a string and use the eval
to create a function, this way scripts like the old jQMinMax won't be
broken by upgrading to 1.3.x.
Regards,
THD