MeshOp.Attach? why doesnt it keep mesh uvs?

ive been makin a lame tool that essentially makes an empty editable mesh and then i use meshOp.attach to attach nodes (planes in this case), for some reason the first plane attached doesnt keep its uvs. every other plane attached keeps its uvs... i cant figure it out. any ideas?

heres my code so far.

p=plane length:100.0 width:100.0
meshOp.attach sp p sourceNode:p
p=plane length:100.0 width:100.0 rotation:(eulerangles (random 0 180) 0 0)
meshOp.attach sp p sourceNode:p

the randomly rotated one keeps its uvs... i just dont understand whats wrong with the first one.

any help would be awesome or atleast the tool im tryin to make would be cool.