No, there is no way to do this. You would need to use more than one phone. There will be a way to have as many as 20 or 34 line appearances with a 7960 phone by adding one or two 7914 Expansion Modules. Right now the data sheet is not available for this on CCO and it is not yet orderable, but there are all sorts of pages about it in the CallManager 3.1 documentation describing it, such as:
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.