Yes, I have just been able to recreate this in 2.4.19. The line in daemon.c at which the assertion occurs in this version is 994.
I have also seen:
ldap_write: want=22 error=Broken pipe ... slapd: connection.c:786: connection_closing: Assertion 'c->c_struct_state == SLAP_C_USED' failed
One things to note is that, in addition to being on MIPS32, my platform has only 32MB of memory. I also have a swap file that is 64MB.