GTM iRule and log local0. crashing BIG-IP

Hi,

I have iRule like that attached to Wide IP:

when DNS_REQUEST {
    check where LDNS is, if below true it is in DR1
    if { [active_members location_pl] < 1 } {
        log local0. "Active members in \"location_pl\" - [active_members location_pl]"
        check if there are any active members in DR1 pool/location
        if { [active_members dr_a_pl] > 0 } {
            pool dr_a_pl
            log local0. "Active members in \"dr_a_pl\" - [active_members dr_a_pl], selected pool [LB::server pool]"
            log local0. "Switching to DR1"
        } else {
            Use DC1 pool
            pool dc_a_pl
        }
    }
}

When executed it is immediately crashing my BIG-IP VE v13.0.0HF2 - failover etc.

When all log local0. is changed to log local2. everything works OK.

From GTM command reference for log command it seems that there should be no problem using ltm log instead of gtm - am I wrong or it's kind of bug?

Piotr