Hmmm. I just tried a similar command on my system and it worked.
I just now made some changes to the way NIFTI filenames are processed/stored inside the dataset structure. This will change the way the filename appear in messages like you got, but shouldn't affect the operation in any other way. (I replace the filename given on the command line with its "realpath" - the actual filepath starting at "/".)
I'll check those in, but I don't think this can fix a problem that I can't duplicate here.