[strongSwan] Strong swan 5.1.1 and Windows XP

[Lupi Loop]

Hi eveyone,

I have a Strongswan 5.1.1 server that is working perfectly for Windows
7/8, Linux and Mac/OSX clients, but I cannot make it work for Windows
XP clients.
I have tried both using the native client of Windows XP (that does not
connect at all) and using two vpn clients, ShrewSoft and TauVPN, (that
establish IKE phase 1 SA but fail at phase 2)

Any ideas of what can be happening or recommendations about the
configuration or any other Windows XP compatible client I can use?

It follows my strongswan configuration for the windows XP client:

Thank you in advance

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config setup

conn %default
ikelifetime=300m
keylife=300m
rekeymargin=3m
dpdaction=none
leftsourceip=X.X.X.X

conn XP
keyexchange=ikev1
esp=aes128-sha1
authby=rsasig
left=Y.Y.Y.Y
leftcert=Cert.pem
leftsubnet=X.X.X.X/XX
right=%any
rightsourceip=Z.Z.Z.Z
rightid="C=AA, O=BB, CN=CC"
leftfirewall=yes
auto=add

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