UserService Plugin removes custom properties when updating user

Hi All,

I've noticed that whenever I try to update existing user and it's custom properties all key-value pairs which are not part of the payload are deleted.

Example:
my "testuser"
has 3 custom properties P1, P2 and P3

I construct a payload

<?xml version="1.0" encoding"UTF-8" standalone'"yes"?>
<user>

     <username>testuser</username>

     <name> Jon Doe </name>

     <properties>

          <property key="P1" value="some value1"/>

          <property key="P3" value="some value2"/>

     </properties>

</user>

I use that payload in my PUT request and for userService/users/{username} url

the effect is that my custom property P2 is removed.

a not really desirable behavior.

I assume that behavior is caused by running

user.getProperties().clear();

inside

private void addProperties(UserEntity userEntity) throws ServiceException

of class

UserServicePluginNG

If this is a feature not a bug... I can't really see the logic behind it, so can someone explain?