HELP~ maya7.0 to x formate duplicate meshes

HI~ I am doing 3D models for game, after research x format is only way I can explore my animation for game 3D engine ..........

the thing is in Maya everything is working fine, but after I explore X format I got 2 meshes with some object.......

anyone knows what is the problems? I try to kill all unuse object in Maya but still got same result. please help~

the picture in Maya
http://tw.f14.yahoofs.com/myper/rYpn_Z.RHB6fRGeJ1de2/blog/ap_20061011081951300.jpg?TTzyDLFBLms5F3Av

the picture after explore to X format
http://tw.f14.yahoofs.com/myper/rYpn_Z.RHB6fRGeJ1de2/blog/ap_20061011081952616.jpg?TTzyDLFBxpx3YzFg

[1084 byte] By [clioyen] at [2007-12-25]