Ohio company Khyber Communications confirmed today it has taken legal action against major PDA vendors HP, Casio and Philips over an alleged patent infringement. Khyber contends that electronic organisers made by these companies, as well as Everex and Uniden, breach a 1997 patent it holds, issued on 9 December 1997. The patent in question covers organisers that have the ability to store and non sequentially retrieve audio messages using handwriting on a PDA's screen. The machines in question are the HP Jornado, the Casio Cassiopeia, the Everex Freestyle, the Philips Nino and the Uniden Unipro. Said Khyber CEO Raj Kumar: "For a small company like us it is unfair that after making such a substantial investment, we are being pushed out by the giants in the field." Khyber is attempting to recover damages from the companies, as well as put an injunction on the particular machines which are alleged to infringe the patents. ®