In theory it should be possible and it would cut a lot of time in having Globe forward it to Singapore. You might just need an endoresment from Globe to be able to do that.
If you plan in using the iphone from Globe in Singapore, why not just get an iphone there in Singapore? It's cheaper and unlocked (locking a phone is illegal in Singapore) and you get to enjoy the warranty without any hassles.
If you plan in getting in touch with Globe numbers, you can always get a Singtel "Kabayan" prepaid sim card where calls to Globe using 01963 + Globe number would only be charged local rates?