IMO, right now, going into this arbitration, Nokia feels no pain, i.e. Nokia has nothing to lose. If nokia loses the arbitration, they pay their dues. Therefore I think IDCC should strategically put more pressure on Nokia and make them feel that they could lose some if they don't settle before arbitration.
To do so, IDCC should have requested that 3G be included in. I don't know the exactly wording in the 3G contract between IDCC/Nokia. But I don't think the contract will name all the companies that can and only serve triggers. Therefore IDCC can argue NEC as 3G trigger for Nokia (after all, NEC is a major player in 3G market even though I don't think it's a named trigger in the contract). Of course, Nokia will disagree. So IDCC can request arbitration to decide whether NEC is a trigger or not and if not, what kind of companies qualify as trigger in term of 3G market share, therefore at least clear up the ambiguity of the contract terms.
When Nokia feels they might lose in arbitration more than they settle with IDCC, they have to think twice about their decision to go into arbitration.