Cisco Systems and Apple Computer have once again extended negotiations regarding the iPhone trademark used by Cisco and Apple to sell their VoIP and cellular phones, respectively. Apple was obliged to respond to lawsuit it called “silly” on Thursday, but instead it negotiated for some extra time.

“Cisco has agreed to give Apple an extension until Wednesday, February 21. Cisco is fully committed to using the extra time to reach a mutually beneficial resolution,” a statement by Cisco says.

According to a report by Reuters, Apple spokeswoman Natalie Kerris confirmed the extension, saying the discussions were aimed at reaching an agreement on trademark rights and interoperability.

Apple claims that its iPhone is a cellular phone, whereas Cisco’s iPhone works using Voice over Internet Protocol, or VoIP, hence, the products are different and customers will hardly be confused. Cisco stresses that it owns all the rights on the iPhone trademark. It should also be kept in mind that many cellular phones nowadays feature VoIP technology and in several years the feature will become a “must have” one and Apple will have to implement the technology, which would put Apple iPhone into direct competition with Cisco’s iPhone.

Cisco obtained the iPhone trademark in 2000 after completing the acquisition of Infogear, which previously owned the mark and sold iPhone products for several years. Infogear’s original filing for the trademark dates to March 20, 1996, the telecom company said. Linksys, a division of Cisco, has been shipping a new family of iPhone products since early last year and in mid-December Linksys expanded the iPhone family with additional products, the firm reminded.

“Cisco entered into negotiations with Apple in good faith after Apple repeatedly asked permission to use Cisco’s iPhone name. There is no doubt that Apple’s new phone is very exciting, but they should not be using our trademark without our permission,” said Mark Chandler, senior vice president and general counsel, Cisco.

Cisco Inc., was seeking to prevent Apple from “infringing upon and deliberately copying and using Cisco’s registered iPhone trademark”.