Question: "Simplify" gives strange result in Maple 10

Hi, I am new to Maple.

It is strange to me that when gamma and gamma1 (not GAMMA) are used in an expression, the "simplify" command gives wrong result in Maple 10.  If gamma and gamma1 are replaced by alpha and beta, it is ok. Also it is fine in Maple 8. Any idea?  The expression is copied below.

> simplify(diff(gamma(x), x)*gamma1(x)+gamma(x)*diff(gamma1(x), x));
                     / d           \     
                     |--- gamma1(x)| gamma
                     \ dx          /     
> simplify(diff(alpha(x), x)*beta(x)+alpha(x)*diff(beta(x), x),symbolic);
        / d          \                    / d         \
        |--- alpha(x)| beta(x) + alpha(x) |--- beta(x)|
        \ dx         /                    \ dx        /