Filling Device Labels to 32 chars is an error?

[este_]

When applying the RDM responder tests, I get an error message when filling the DEVICE_LABEL with spaces until 32 chars are reached (SET "label" will then produce a GET "label ". Since spaces are ASCII chars and E1-20 does not mandate to cut trailing spaces I cannot see any reason why this implementation should conflict with the existing standard. We found filling labels with spaces extremely helpful since some controllers do not manage their text windows properly and this surely prevents displaying "lost" characters from previous longer labels. The added transmission time is neglegible.

Did I miss something ?
Eckart