Re. your question. I have no evidence for it but my understanding is that it is GSM and therefor should work in Singapore. I have a 6200 monochrome and likewise works worldwide. The old ones are not provider branded and all unlocked.
When you insert a PAYG SIM and it shows gprs, (no caps) you should be fine with BIS.
I'm keen to know how you're getting on with it. Could you pase results as it may be of interest.
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