The exponent of the RSA public key must be odd.??

OS/390 Integrated Cryptographic Service Facility Application Programmer's Guide Version 2 Release 5 Publication No. SC23-3976-02 : http://ppdbooks.pok.ibm.com:80/cgi-bin/bookmgr/bookmgr.cmd/DOCNUM/SC23-3976/... In several parts of the document it's specified that, as a restriction:

The exponent of the RSA public key must be odd.

It's there any (unknown to me) security reason to be this way, or itŽs an implementation/standard option??