2663559 - Runtime Errors STRING_BAD_REF on ABAP Program CL_RSPLS_BUFFER_AM

While starting a query or input form you get an error. Checking in ST22, you see a dump with this header:

Short Text says:
    Access to string reference with corrupt content

On the same dump, checking the call stack, there is a reference to the enqueue methods:

Access to string reference with corrupt content, RSPLS_S_LOCK, CL_RSPLS_BUFFER_AM============CP, STRING_BAD_REF, DBBUF, BAD_VALUE,STRING_BAD_REF, ENQUEUE, CL_RSPLS_BUFFER_AM=>ENQUEUE , KBA , BW-PLA-IP , Integrated Planning , EPM-BPC-BW4-PLA , BPC/4 - Planning Enginee , Problem