Technology stack:
(Bitnami with Redmine 2.2.3-0-ubuntu-12.04 in VMWare Player)

Environment:
Redmine version 2.2.3.stable
Ruby version 1.9.3 (x86_64-linux)
Rails version 3.2.12
Environment production
Database adapter Mysql2
Redmine plugins:
no plugin installed

Using REST API (XML) with curl

Description:
For some fields, invalid values can be submitted. These values are not ignored, rather the current field value is deleted. For example:

Field "start_date":
If a year of more than 9999 is submitted (for example, "10000-01-01", the journal entry suggests that the date was updated. However, it was actually deleted.

Fields "Category_id, fixed_version_id, assigned_to_id, done_ratio", also applies to custom fields (boolean):
If a value of "a" is submitted, the current value is DELETED or reset to the default value. For example, when submitting "a", done_ratio is set to 0

Expected result:
Invalid values should not result in the fact that old values are deleted or reset. An error message should be thrown.