Sprint Nextel, which does not have a VoIP product on the market, announced Wednesday that it has filed suit in the U.S. District Court for the District of Kansas, alleging that Vonage Holdings, Inc., Voiceglo Holdings, Inc., and theglobe.com, Inc., infringed on seven patents held by Sprint Nextel.

“The patents protect a series of innovations that enable the processing and delivery of packetized voice and data communications, including Voice over Internet Protocol (“VoIPâ€?) communications. In the lawsuit, Sprint Nextel seeks an injunction that would prevent these companies from further misappropriating Sprint Nextel’s technology and infringing Sprint Nextel’s patents. The lawsuit also seeks unspecified monetary damages arising from the companies’ unauthorized use of the patented technology and the continued willful infringement of Sprint Nextel’s patents,” the company said in a press release.

The comapny did not say which patents it alleges had been infringed.

Some analysts believe that Sprint Nextel may be looking to purchase Vonage, to add a VoIP product to its portfolio. Vonage is widely believed to be preparing to go public.