which renderer in Maya? Mental Ray has a Sun & Sky option in the Indirect Lighting tab in the render settings there's also the Final Gather option I'm not a Max user but these two option *may* be what you're after
Just did this in Maya, may be the same for Max: in the Area Light attributes is a section that says "High Samples, High Sample Limit, Low Samples." My default High Sample was 8, bumping it to 64 fixed the shadow problem