pls help. problem watching iphone recorded video on xperia x10

[#1]

hi all.. not sure if you have experienced the same problem.  my husband has an iphone 4 and he records video of our daughter sometimes and emails them to me.  I have problems watching them in the xperia x10.  I can watch the videos but i can't hear the sound even when i turn up the volume.  can you please help?

thanks in advance.

[#2]

I've no experience of playing movies recorded on an iphone but have you tried downloading Rock Player? - that seems to play stuff that the X10 struggles with