How to convert and transfer iTunes m4p & protected wma music to Nokia XpressMusic 5800/5710/5610/5320 etc for free

iTunes has two types of music: music DRM-free from iTune plus; music copy-protected with digital rights management (DRM). All the iTunes music is encoded in AAC (Advanced Audio Coding) with file extension of .m4a(non-DRM 256Kbps) and .m4p(DRM-protected 128Kbps).
Nokia XpressMusic 5800 Range plays audio file in formats of MP3, AAC, WMA, M4A etc
Generally, the Nokia Nokia [...]