Does ab ≡ 0 (mod m) imply a|m or b|m?

[imagination10]

ab ≡ 0 (mod m), where a and b are positive integer < m.
Does it follow that either a| m or b| m?


Can anyone give a proof for this ?

 

[mathman]

Not true. Example: a=8, b=9, m=12.