Quoting myself:Let me add some words about multilanguage support:
Since multilanguage is not yet fully implemented (currently in phase 3 of 4) I guess it will be possible in the future (when phase 3 or 4 are completed), but currently it is not possible to translated content related stuff like help topics names, landing page, and so on.
You need to either manually translate it and only use then the spanish translation or wait until multilanguage support is fully implemented. See also this pull request at github which shows the upcoming changes with content translation (phase 3): https://github.com/osTicket/osTicket-1.8/pull/1410
See: http://forum.osticket.com/d/discussion//language-pack-does-not-change-the-landing-page#latest