The generator matrix

 1  0  1  1  1  X  1  1  1  1  0
 0  1  1  X X+1  1  0 X+1  X  1  1
 0  0  X  0  X  0  X  0  X  0  X

generates a code of length 11 over Z2[X]/(X^2) who´s minimum homogenous weight is 10.

Homogenous weight enumerator: w(x)=1x^0+6x^10+16x^11+6x^12+2x^14+1x^16

The gray image is a linear code over GF(2) with n=22, k=5 and d=10.
As d=10 is an upper bound for linear (22,5,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 5.
This code was found by Heurico 1.16 in 0.000276 seconds.