And so it goes on. Mercury News reports that,

Cisco Systems sued Apple Wednesday over the trademark to the name “”iPhone,” setting up a legal battle between two of Silicon Valley’s biggest companies.

Cisco claims that Apple deliberately infringed its rights to use the brand when Steve Jobs introduced Apple’s iPhone, a long-anticipated gadget that combines a cell phone and a video and music player, at Macworld in San Francisco Tuesday, allegedly without Cisco’s permission.

The suit seeks an injunction to stop Apple’s use of the name.

“We’ve been in intensive discussions with Apple for several weeks regarding arrangements to share the brand,” said Mark Chandler, Cisco senior vice president and general counsel.

Cisco expected Apple to quickly sign an agreement sent over late Monday to use the name, but Apple never did.

Apple did not back down. Calling Cisco’s suit “”silly,” company spokeswoman Natalie Kerris noted that “”several companies” other than Cisco had already been using the iPhone name for voice over Internet protocol (VoIP) phones…