Coming from Ashraful Madaris, in Kanpur, India, is a fatwa, stating that ring tones which use verses from Quran, are 'anti-Islamic', since they are usually cut in middle when one picks up the call. They also argue that listening to such verses in the toilet, which mobile phones aren't adverse to, is a grave sin that must be disallowed.
For those who don't know, a Fatwa is a religious decree passed by an Islamic scholar. It formulates an opinion on finer points of religious issues, and its applicability may or may not be binding depending on the status of the scholar implementing it.
Some scholars have on the other hand expressed that this is a stone-age opinion, as the people keep such ring-tones out of love and respect for the Quran, and mean it no disrespect. They say that as long as one is careful to keep the phone in silent mode while in the vicinity of the toilet.