I NEED TO KNOW , HOW TO CONFIGURE A PHONE AND THAT INDICATE WHEN A EXTENSION ITS BUSY OVER CCM 4.1
BLF was introduced in 4.2(x), therefore there is no such functionality in 4.1(x).
A similar functionality can be achieved by using shared lines.
If that's not a viable option, then you need to upgrade.
Also, please follow basic etiquette when posting. Writing in capital letters is the equivalent of yelling.
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