TWM Throws Me to 2G With A Reject Cause 15 – That’s a First!

I've recently been in Taiwan for a couple of days and obviously I had to check out the local networks here. The first thing I noticed is that Taiwan Mobile (TWM) doesn't let my German SIM card roam on their 3G network. I get a nice and clean mm reject cause 15 (no suitable cells in this location area) together with a gmm reject cause 9 (MS identity can't be derived from the network) so the mobile gives up on 3G and re-selects to GSM. How interesting, haven't seen that anywhere in the world yet. Either there was not 2G and 3G roaming agreement at  all or I could roam in a 3G network of a network operator if it was available. O.k. no roaming business from me then for TWM, Chunghwa's 3G networks has no problem with me 🙂 And I guess other smartphone users will just do the same when coming to Taiwan when they experience this. Not good for TWM…