Found Bug - What is this?

Yesterday I was playing live blitz against VoyageInfinite, I had  King, Rook and 2 pawns and he had King and Knight, when he moved his knight suddenly message displayed "Game Drawn - Insufficient Material" why?

This comes up on this forum many many times. It is not a bug.

You ran out of time, which is usually a win for him. But because he had insufficient mating material (K+N) the game is a draw

It seams to be a bug anyway if the information above is correct:

If you have a night left can you still mate your oppnent if he has pawns left, so friendlymansi should have lost the game. 

Or do I overlook something here?

Yes you overlooked the many discussions on here about insufficient material rule and how the interpretation differs between FIDE and USCF.

Here is one http://www.chess.com/forum/view/livechess/how-come-this-is-a-draw

I think it's amusing that some endings which are dead draws (K+R vs K+R) are scored as wins because someone ran out of time and other endings which are "insufficient" are scored as draws. From a ratings perspective this is an unbalanced, illogical outcome. If the clock is going to be used, its effect should be applied equally.

K+R vs K+R is a win for the side that didn't time out because it is theoretically possible for the winning side to checkmate the other side. Whereas if you have K+Q, and your opponent only has a king and you run out of time, the game is a draw because even if your opponent had as much time as he wanted he wouldn't be able to checkmate you.

Does the draw rule apply if one side has a King and Pawn and the other side has only a King? In some such positions--but not all--the outcome of the game is always a draw.  

If the flag falls when the position on the board is what we would call a "drawn" position........

If the side with the pawn runs out of time, it is clearly a draw.

If the side with the lone king runs out of time, under FIDE rules it would be a win for the side with K+p, as it is possible (though unlikely), would the game continue, for the pawn to be promoted "by any possible series of legal moves" (FIDE wording).

USCF rules are different, and would I believe declare that as the position is "drawn", the result is a draw.

In an OTB game, before the flag falls, a player may stop the clock and request the arbiter to declare a K+R vs K+R game a draw.  This cannot be done on-line.

Chess.com incorporated this concept (requesting adjudication) into their "insufficient material" rule (they, in effect, have done the adjudication).  However, computer programming has its limitations, and there are inconsistencies.

Agreed, and this inconsistency is amusing to me. Chess.com didn't want to get into adjudication of games, yet went ahead and implemented rules to adjudicate certain endings. There have been many times I wished I could demote my rook to a knight just so I could avoid losing on time. Playing "punch the clock" to win a point isn't chess.

I usually play using increments to avoid the problem.  I have a few 100+ move games where my opponent tried to run me out of time rather than accept a draw.  Moved either my rook or bishop several times until we reached 50 moves (easier than looking for repetition).

I tried that, but it seems to be an unpopular choice. I like to play 2/12 games but have reverted to 10/0 because no one else seems to accept the other.

If the opponent of the player who ran out of time has a bare king, king+knight, king+bishop, or king+2 knights, it's a draw, because chess.com would rather have incorrect draws in rare cases, than incorrect wins in probably less rare cases.

And either way the results are incorrect. :-)

actually a king and pawn vs a king can be winnable assuming you know the correct techniec, there are also positions where it is a draw so it unfair to say that most K+P vs K positions are a draw...