Itunes refuse to transfer .mp4 files into my iphone

[sami]

Hi,

I have loads of .mp4 files and I need to make them available with me everytime and everywhere. The problem is that itunes does not want to transfer them citing that the iphone would not be able to play them as a reason for that. I know that the iphone would be able to play them as I uploaded one file through filezilla(wifi) and played it using xbmc, but the transfer rate is very slow using fiezilla and it would not be practical for my over 32Gb in size files. Any way I can force itunes to upload these files?

Thanks and best regards
Sami