I guess what gives me pause, @adrian009 is the fact that there are virtually no Christian scholars who support this line of thinking. Are there any Christian scholars who see merit in this Muslim perspective? It is little surprise that Muslims would hallucinate Muhammad into texts, but I'm simply unaware of any reputable Christian (or Jewish) scholars agreeing with the assertion.
@Tumah I am wrong on this (that it's pretty much a Muslim only belief (promoted by some Bahai's too)) who see Muhammad mentioned in the Bible?
No Christian scholars will support Islam in the Bible because if they did they would be Muslim scholars instead. It is the same deal for Jewish scholars. Many Jewish scholars will argue there is not one verse in the Tanakh that refers to Jesus.
Traditionally Muslim scholars have taken the perspective the NT and Torah are corrupted and superseded by the Quran. So its a relatively recent historic development that more Muslims are arguing the Bible is authentic and it does mention Islam. Of course its something the Baha'is have been saying from the mid 19th century.