Sorry - i misread your email, thinking it was set at 2MB. 2GB tends to be an apache http limit on 32 bit systems running php 5.3. If you have files greater than 2gb, consider other ways of uploading them or make weblinks to them, or move to a 64 bit system, move up to php 5.4, and that may solve your problem. (unless you already have a 64 bit and php 5.4+ version)
Or, maybe try the following in your php.ini - this should allow uploads up to the post_max_size variable.
upload_max_filesize = 0
you could also try:
post_max_size = 0
upload_max_filesize = 0
But, again, I might suggest that files this large might be better handled by non http protocols, and you could have a secure file repository with weblinks within feng.