Internet agency seeks contract management software

We are looking for contract management software for our internet agency.

The solution should meet the following requirements:

• Central storage of contracts
• Overview of terms and notice periods
• Reminders when usage rights (e.g. for images) granted to us by artists expire
• Ideally, the software should include a good text recognition programme so that PDFs etc. can be read automatically.
• Assignment of different access rights (write, read)
• Must be compatible with both MS Windows and Mac OS X

Three editors/data entry clerks and approximately ten readers are planned for software workstations.