Quote by: fitzIt appears that the VO package that is loaded by default in the login.cl file is resetting the value, I'll fix this is the next release to preserve the value set in the login.cl/loginuser.cl file.
The reason you may be seeing a .imh being written might depend on how you are testing, e.g. the command
cl\$this->_split2($m[0]) imcopy dev$pix foo
will create a 'foo.imh' because it is preserving the input image type when no extension is given. This is different from a task that creates a new image from scratch such as with the ARTDATA package.
In fact, I commented out the call to vo (that I am not using now) and everything works fine.