GP doesn't work with MOSEK solver

When attempted to solve with MOSEK, any GP (except for trivial one) problem returns:

Subscript indices must either be real positive integers or logicals.
Error in cvx/shims/cvx_mosek.p>solve (line 367)

Matlab version: 7.13.0.564 (R2011b)

CVX Code: build 908 (w/Academic license)

Mosek 6.0.0.141

Sample GP that doesn’t work:

cvx_begin gp
   variables a b
   minimize a+b
cvx_end

Sample GP that works:

cvx_begin gp
   variables a b
   minimize a
cvx_end

This is clearly a bug. Please submit a ticket to http://support.cvxr.com