How to set DZ11 line speeds under RT-11 V4?

Hi all, I've now had some success getting MU-BASIC configured and running on multiple terminals under RT-11 V4 in simh, with a hardware configuration similar to that in my real PDP-11/45. I have a serial console + DZ11 in both configurations. When SYSGEN-ing RT-11 V4, the only speed initialization options offered for the DZ11 lines are 110 or 300 baud. Is there a utility or incantation which will allow me to reconfigure these after RT-11 is booted? I scanned the RT-11 V4 docs last night, but came up empty (there is an "unsupported" SPEED.SAV in the distribution, but it looks like it only works with PDTs, and I couldn't find anything tucked away in the SET command or other places either). It looks like I could write some MACRO code to try and set this using the .MTGET/.MTSET programmed requests, but I thought I'd ask here in case there is some known prefab way to do this that I missed looking through the docs? cheers, --FritzM.