help with a strange three way handshake

I've got this dump


# syn
11:32:50.415885 SERVERONE.34877 > SERVERTWO.smtp: S
500330151:500330151(0) win 5840 <mss 1380,sackOK,timestamp 3229915070
0,nop,wscale 0> (DF) (ttl 52, id 36410, len 60)

# syn ack double why? Maybe a long time whitout an answer so we have
retrasmission?
11:32:50.416164 SERVERTWO.smtp > SERVERONE.34877: S
3005103307:3005103307(0) ack 500330152 win 5792 <mss
1460,sackOK,timestamp 2251114386 3229915070,nop,wscale 2> (DF) (ttl
64, id 0, len 60)
11:32:54.515189 SERVERTWO.smtp > SERVERONE.34877: S
3005103307:3005103307(0) ack 500330152 win 5792 <mss
1460,sackOK,timestamp 2251115411 3229915070,nop,wscale 2> (DF) (ttl
64, id 0, len 60)

# half "ack", indeed no S flag but mss and sackOK that have not to be
here ..
11:32:54.520263 SERVERONE.34877 > SERVERTWO.smtp: . ack 1 win 5792
<mss 1460,sackOK,timestamp 2251115411 3229915070,nop,wscale 2> (DF)
(ttl 39, id 0, len 60)

Someone can explain me this strange "three way" that indeed is not
functioning at all, the subsequent packets dump is

11:32:54.520502 SERVERTWO.smtp > SERVERONE.34877: . ack 1 win 5792
<nop,nop,timestamp 2251115412 3229915070> (DF) (ttl 64, id 0, len 52)
11:33:00.519293 SERVERTWO.smtp > SERVERONE.34877: S
3005103307:3005103307(0) ack 500330152 win 5792 <mss
1460,sackOK,timestamp 2251116912 3229915070,nop,wscale 2> (DF) (ttl
64, id 0, len 60)
11:33:00.524286 SERVERONE.34877 > SERVERTWO.smtp: . ack 1 win 5792
<mss 1460,sackOK,timestamp 2251116912 3229915070,nop,wscale 2> (DF)
(ttl 39, id 0, len 60)
11:33:00.524489 SERVERTWO.smtp > SERVERONE.34877: . ack 1 win 5792
<nop,nop,timestamp 2251116912 3229915070> (DF) (ttl 64, id 0, len 52)
11:33:12.519379 SERVERTWO.smtp > SERVERONE.34877: S
3005103307:3005103307(0) ack 500330152 win 5792 <mss
1460,sackOK,timestamp 2251119912 3229915070,nop,wscale 2> (DF) (ttl
64, id 0, len 60)
11:33:12.524171 SERVERONE.34877 > SERVERTWO.smtp: . ack 1 win 5792
<mss 1460,sackOK,timestamp 2251119912 3229915070,nop,wscale 2> (DF)
(ttl 39, id 0, len 60)
11:33:12.524390 SERVERTWO.smtp > SERVERONE.34877: . ack 1 win 5792
<nop,nop,timestamp 2251119912 3229915070> (DF) (ttl 64, id 0, len 52)
11:33:36.731392 SERVERTWO.smtp > SERVERONE.34877: S
3005103307:3005103307(0) ack 500330152 win 5792 <mss
1460,sackOK,timestamp 2251125965 3229915070,nop,wscale 2> (DF) (ttl
64, id 0, len 60)
11:33:36.736748 SERVERONE.34877 > SERVERTWO.smtp: . ack 1 win 5792
<mss 1460,sackOK,timestamp 2251125965 3229915070,nop,wscale 2> (DF)
(ttl 39, id 0, len 60)
11:33:36.736985 SERVERTWO.smtp > SERVERONE.34877: . ack 1 win 5792
<nop,nop,timestamp 2251125965 3229915070> (DF) (ttl 64, id 0, len 52)
11:34:24.943542 SERVERTWO.smtp > SERVERONE.34877: S
3005103307:3005103307(0) ack 500330152 win 5792 <mss
1460,sackOK,timestamp 2251138018 3229915070,nop,wscale 2> (DF) (ttl
64, id 0, len 60)
11:34:24.950072 SERVERONE.34877 > SERVERTWO.smtp: . ack 1 win 5792
<mss 1460,sackOK,timestamp 2251138018 3229915070,nop,wscale 2> (DF)
(ttl 39, id 0, len 60)
11:34:24.950314 SERVERTWO.smtp > SERVERONE.34877: . ack 1 win 5792
<nop,nop,timestamp 2251138019 3229915070> (DF) (ttl 64, id 0, len 52)
11:37:50.410027 SERVERONE.34877 > SERVERTWO.smtp: F 1:1(0) ack 1 win
5840 <nop,nop,timestamp 3229945068 2251138019> (DF) (ttl 52, id 36412,
len 52)
11:37:50.410264 SERVERTWO.smtp > SERVERONE.34877: R
3005103308:3005103308(0) win 0 (DF) (ttl 64, id 0, len 40)

As you see we have a reset at the end.
.