In HHH-6655 the trim-function used by the DB2-dialect where reworked.
Before this fix, the JPQL-function

TRIM(TRAILING '*' FROM foo.a)

where rendered to

replace(replace(rtrim(replace(replace(FOO.A,' ','${space}$'),'*',' ')),' ','*'),'${space}$',' ')

This statement is a bit ugly and results in a warning {cite}HHH000174: Function template anticipated 3 arguments, but 2 arguments encountered{cite}, but it works.
After this fix, the function is rendered to

trim(TRAILING '*' FROM FOO.A)

This statement is quite neat, but doesn't work on v9.1, because only ltrim, rtrim and replace is supported, but no trim.