Do you intent to do this anyway without the themeroller support or are you gonna wait for them to implement this. I really liked that function and it stops me from using the much nicer 3.5 version.

Without the theme roller support people can create there own css…

It's not the cleanest solution but in the meantime I did this to get the alt to work.

Each alt row gets the ui-priority-secondary class from jquery.ui themes

in the jqgrid css file i added this line.

.ui-jqgrid tr.ui-priority-secondary td { background: #COLOR_CODE; }

And it works.