Check the code behind and see if the gap is a space character. If it is, then do this:
in file /controls/SolpartMenu/spmenu.js
at line 1650 or there-abouts
if (spm_browserNeedsSpacer() == false && sImage == 'spacer.gif' && bForce != true)
return ' ';
else
return "<IMG SRC=\"" + sPath + sImage + "\" " + spm_getAlt(sAlt) + ">";
Remove the - leave the quotes in place
Rob