It seem that’s a bug in version 4.x preventing a router with too many VLANs configured on a interface to start.
The router works OK after adding the VLANs, but after restart it isn’t reachable anymore on any interface.
I have reproduced it with different i386 sistems, both Intel and AMD - only the maximum VLAN numbers changes ( from about 700 to 1000).
Version 2.9x worked OK in this respect.
confirm this, only on 2.9 router can work whith 1000 vlans