Something

else if (md->type==eModifierType_Randomize) {            RandomizeModifierData *rmd = (RandomizeModifierData*) md;                        but = uiDefBut(block, TEX, B_MODIFIER_RECALC, "VGroup: ",    lx, (cy -= 19), buttonWidth, 19, &rmd->name, 0.0, 31.0, 0, 0,  "Name of vertex group to randomize (randomize whole mesh if blank)");			uiButSetCompleteFunc(but, autocomplete_vgroup, (void *)ob);             			if (!rmd->name) uiDefButF(block, NUMSLI, B_MODIFIER_RECALC, "Factor:",	lx,(cy-=19),190,19, &rmd->factor, 0.01, 0.1, 0, 0, "Specify how much randomness to add (leave blank to use Factor)");