Why does the plugin return asp-version 2 even if client is v1

[st3fan]

OS X Server 5.1.7 `* OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE XAPPLEPUSHSERVICE AUTH=CRAM-MD5 AUTH=PLAIN AUTH=LOGIN AUTH=DIGEST-MD5] Dovecot ready. a1 LOGIN stefan xxx a1 OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS SPECIAL-USE BINARY MOVE XAPPLEPUSHSERVICE SEARCH=FUZZY URLAUTH URLAUTH=BINARY COMPRESS=DEFLATE QUOTA ACL RIGHTS=texk] Logged in a2 XAPPLEPUSHSERVICE aps-version 2 aps-account-id 0715A26B-CA09-4730-A419-793000CA982E aps-device-token 2918390218931890821908309283098109381029309829018310983092892829 aps-subtopic com.apple.mobilemail mailboxes (INBOX Notes)

• XAPPLEPUSHSERVICE "aps-version" "1" "aps-topic" "com.apple.mail.XServer.ce18a160-37f5-4643-9d93-89c1dcd82676" a2 OK XAPPLEPUSHSERVICE completed. a3 LOGOUT
• BYE Logging out a3 OK Logout completed.`

Dovecot 2.0.19 with dovecot-xaps-plugin

`* OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE AUTH=PLAIN] Dovecot ready. a1 LOGIN stefan xxx a1 OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS MULTIAPPEND UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS XAPPLEPUSHSERVICE] Logged in a2 XAPPLEPUSHSERVICE aps-version 2 aps-account-id 0715A26B-CA09-4730-A419-793000CA982E aps-device-token 2918390218931890821908309283098109381029309829018310983092892829 aps-subtopic com.apple.mobilemail mailboxes (INBOX Notes)

• XAPPLEPUSHSERVICE aps-version "2" aps-topic "com.apple.mail.XServer.ce18a160-37f5-4643-9d93-89c1dcd82676 " a2 OK XAPPLEPUSHSERVICE Registration successful. a3 LOGOUT
• BYE Logging out a3 OK Logout completed.`