Hope this helps , For Australia Vodafone kindly go to :

https://unlock.vodafone.com.au/voila/handse...d=selectService

It states that unlock basic fee is $50, then you've to pay another $50 for unlocking it... so total $100 minus $25 if you unlock online~ meaning you have to pay $75 for unlocking... can pay by credit cards, I believe all you have to do is key in the IMEI number for them to verify and unlock it...

I suggest you give them an email see what they recommend you to do.
Wish you luck for it ... ~