The best way I've found to make something like a bulb glow is to make the shader for the glass itself glow.  Multiply the glow color with a 1 - 100% modifier and use that to adjust to the glow you want.  Put a bulb inside it for the glow on other objects.  You will want to use ray trace shadows on the bulb and enable soft shadows using a diameter approximating the bulb's size.  If the bulb creates wierd shadows, make the bulb light illuminate everything except the bulb itself.

I have never had good luck with anything glows.

If the bulb is part of a larger object, take that object into the model room, select just the polys that make up the bulb surface and assign them to a new shader zone so you can apply a glass shader with glow to just that zone.

Good luck!

Klebnor

Lotus 123 ~ S-Render ~ OS/2 WARP ~ IBM 8088 / 4.77 Mhz ~ Hercules Ultima graphics, Hitachi 10 MB HDD, 64K RAM, 12 in diagonal CRT Monitor (16 colors / 60 Hz refresh rate), 240 Watt PS, Dual 1.44 MB Floppies, 2 button mouse input device.  Beige horizontal case.  I don't display my unit.