Correction to Zikula_Session_LegacyHandler refs #905

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | na
| Refs tickets  | #905
| Fixed tickets | #905
| License       | MIT
| Doc PR        | na