command click not working in FF on Mac OS X

The equivalent to ctrl click for multi selecting lines in the xgrid on the Mac, Command click, does not work in Firefox. ctrl click does not work because this brings up the context menu. Is there a work around for this?

Which version of dhtmlxgrid do you use?
In latest version of dhtmlxgrid it must react on Mac-Click in multiselect mode.

If necessary behavior with ctrl-click can be switched back from context menu calling to multiselect

dhtmxlgrid.js , line 1011
    if (ev.button==2 || (_isKHTML && ev.ctrlKey)){
just remove right part of rule