DKIM not generated for specific domain

[root@s2 scripts]# ./dkim_create.sh aaaaa.nl
[root@s2 scripts]# ./dkim_create.sh bbbbb.nl
Generating RSA private key, 2048 bit long modulus
.................+++
...................+++
e is 65537 (0x10001)
writing RSA key

Same user account, for one domain (bbbbb.nl) the DKIM is generated, for aaaaa.nl nothing happens?