+mail belongs in that group.
+
+This variable can also have a function as its value, the function will
+be called with the headers narrowed and should return a group where it
+thinks the article should be splitted to. See `nnimap-split-fancy'.
+
+To allow for different split rules on different virtual servers, and
+even different split rules in different inboxes on the same server,
+the syntax of this variable have been extended along the lines of:
+
+(setq nnimap-split-rule
+ '((\"my1server\" (\".*\" ((\"ding\" \"ding@gnus.org\")
+ (\"junk\" \"From:.*Simon\")))
+ (\"my2server\" (\"INBOX\" nnimap-split-fancy))
+ (\"my[34]server\" (\".*\" ((\"private\" \"To:.*Simon\")
+ (\"junk\" my-junk-func)))))
+
+The virtual server name is in fact a regexp, so that the same rules
+may apply to several servers. In the example, the servers
+\"my3server\" and \"my4server\" both use the same rules. Similarly,
+the inbox string is also a regexp. The actual splitting rules are as
+before, either a function, or a list with group/regexp or
+group/function elements.")
+
+(defvar nnimap-split-predicate "UNSEEN UNDELETED"
+ "The predicate used to find articles to split.
+If you use another IMAP client to peek on articles but always would
+like nnimap to split them once it's started, you could change this to
+\"UNDELETED\". Other available predicates are available in
+RFC2060 section 6.4.4.")
+
+(defvar nnimap-split-fancy nil
+ "Like `nnmail-split-fancy', which see.")