When restoring XML space backup from a previous major release, a misleading error is thrown

Steps to reproduce

1. Create an XML space export from old version of Confluence. For example Confluence version prior than Confluence 5.x
2. Import it in Confluence 5.6.5

What Happens

1. The space backup could not be restored which is an expected behavior. (See other notes below)
2. The following error(s) occurred:
   • From Confluence version 4 and above

     Backups made prior to Confluence 4.0 (build 3047) can not be restored. This backups build number was missing.
     

   • From Confluence prior to 2.7.4

     Backups made prior to Confluence 2.7.4 (build 1117) can not be restored. This backup had build number 813.
     

What is expected

1. Something related to space export-import across major release is not allowed
2. The above error is misleading as the backup was not made "prior to Confluence 4.0"

Other notes:

1. Confluence does not support major release space backup, as per this documentation

   Confluence supports importing site and space backups into the same major version only. In Confluence,

2. Workaround to restore spaces from an earlier major releases provided from the documentation below:

• Workaround for restoring spaces between major releases