PA1688 Software 1.57     1.57 Revision list (Mar 27, 2007): 1. Added IAX2 call forwarding function 2. Added remote ringback tone for IAX2 3. Fixed a SIP bug related with call clearing     Software download (zipped files): Please email us if you can not find what you need here. Software API PA168V 1-port FXS gateway IAX2 English IPLINK IP phone IAX2 English