In Poser, you can accomplish a glow by plugging the image map into the Ambient color of your root node in the material room and setting its Ambient color to 1 or greater.  However, if you are expecting surrounding areas to catch any emitted light, it is not easily possible in Poser 5 within creating gather nodes in those materials.  It can be done in P8 and PoserPro 2010 with IDL.