odd build error

[Richard Mortier <Richard.Mortier@xxxxxxxxxxxxxxxx>]

i'm making a start at an openflow implementation in mirage.  just starting to 
get dave's packet parsing mpl ported over to bitstring.  am hitting a compile 
error that i don't understand:

/usr/local/bin/ocamldep.opt -pp 'camlp4o -I ../../../syntax/_build pa_lwt.cma 
pa_bitstring.cma pa_js.cma' -modules openflow/ofpacket.ml > 
openflow/ofpacket.ml.depends
+ /usr/local/bin/ocamldep.opt -pp 'camlp4o -I ../../../syntax/_build pa_lwt.cma 
pa_bitstring.cma pa_js.cma' -modules openflow/ofpacket.ml > 
openflow/ofpacket.ml.depends
File "ghost-location", line 448, characters 40--13388 (end at line 1, character 
0):
Failure: "invalid long identifier type"
Preprocessing error on file openflow/ofpacket.ml
Command exited with code 2.
make[1]: *** [node-socket-node] Error 10

all checked in on openflow branch; code around that line is:

"""
type phy_port = {
        port_no: uint16;
        hw_addr: eaddr;
        name: string;
        config: port_config;  
        stp_forward: bool;
        stp_learn: bool;
        link_down: bool;
        curr: phy_port_feature;
        advertised: phy_port_feature;
        supported: phy_port_feature;
        peer: phy_port_feature;
}

type port_status_reason = [ ADD | DEL | MOD ]  <======= this is line 448
let port_status_reason_of_int = function
  | 0 -> ADD
  | 1 -> DEL
  | 2 -> MOD
and int_of_port_status_reason = function
  | ADD -> 0
  | DEL -> 1
  | MOD -> 2
and string_of_port_status_reason = function
  | ADD -> sp "ADD"
  | DEL -> sp "DEL"
  | MOD -> sp "MOD"
"""

hints, suggestions, answers welcome :)

-- 
Cheers,

R.

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