It has come to our attention that in R14 and R14 SP1, ACIS or CATIA parts or assemblies which have four or more solid bodies in a single part will not save to JT.
While this is being resolved, the workarounds are to either save the file to Parasolid (.x_t) and then save the file to JT, or convert the part to a true assembly (Right click on the Assembly Browser > Change > Create Assembly).
Please feel free to send an email to support@TransMagic.com if you need more clarification on this issue and workaround.