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- Linux/BSD distribution name and version: Ubuntu 14.04.1
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====

I have like others problem to get the DKIM for the second domain working, even thought it passes when I try the string on the some sites. So I try to look it up the best so we can solve it fast.

On your guide it tells us to put the new domain in:
Add your new domain in @local_domains_maps in /etc/amavis/conf.d/50-user. The line should now read something like this:

"@local_domains_maps = ( [".$mydomain", "firstdomain.com", "new_domain.com"] );  # list of all local domains"

But, when I open that file I can´t seem to find that part, instead I found this:

chomp($mydomain = "ubuntutouch.se");
@local_domains_maps = 1;
@mynetworks = qw( 127.0.0.0/8 [::1] [FE80::]/10 [FEC0::]/10
                  10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 );

And regarding to the DKIM:

dig -t txt dkim._domainkey.ubuntutouch.se

; <<>> DiG 9.9.5-3ubuntu0.1-Ubuntu <<>> -t txt dkim._domainkey.ubuntutouch.se
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 53980
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;dkim._domainkey.ubuntutouch.se.        IN      TXT

;; AUTHORITY SECTION:
ubuntutouch.se.         1799    IN      SOA     ns1.digitalocean.com. hostmaster.ubuntutouch.se. 1420523238 10800 3600 604800 1800

;; Query time: 184 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Tue Jan 06 07:22:27 CET 2015
;; MSG SIZE  rcvd: 126

And the key is:
v=DKIM1; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDQg59KY5eY5CirVAUiNmw939HT8Fw8G4HkWYiSLYBgWa6oHt/geNR078cK7hznBlF1v9KvaLKWe940ZHTrIqwUDCK/VzvvxSz4C/Jf3GvIH9EMfqi9iIBRE+upfWfb3SsVPxOEV5G2dB9/s8KcxBHrlvS/qc0ocQIO50mKNFQeBQIDAQAB

And it passes on this site: http://dkimcore.org/tools/dkimrecordcheck.html. My DNS is correct, and I have deleted the DNS record and added it multiple times just to be sure it´s correct.

This is the output for all keys:

# amavisd-new showkeys
; key#1, domain minipickup.se, /var/lib/dkim/minipickup.se.pem
dkim._domainkey.minipickup.se.  3600 TXT (
  "v=DKIM1; p="
  "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC9wBXtARGHi1QwswRcJ+R6BV62"
  "YeUnhZKAB9qRf4ZY6elaSL/YXrDJvtKkioAJIsGmfkqon1fLrBGjbRWnv4mQKPx1"
  "ntx9J+JFWWjt/UDlCQanACBYl3LzYz7L0xHFVtFxBNhJEeuapGV2Lm+N3Gh/r3NV"
  "HfUDoeVlOzZf4HmjiQIDAQAB")

; key#2, domain ubuntutouch.se, /var/lib/dkim/ubuntutouch.se.pem
dkim._domainkey.ubuntutouch.se. 3600 TXT (
  "v=DKIM1; p="
  "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDQg59KY5eY5CirVAUiNmw939HT"
  "8Fw8G4HkWYiSLYBgWa6oHt/geNR078cK7hznBlF1v9KvaLKWe940ZHTrIqwUDCK/"
  "VzvvxSz4C/Jf3GvIH9EMfqi9iIBRE+upfWfb3SsVPxOEV5G2dB9/s8KcxBHrlvS/"
  "qc0ocQIO50mKNFQeBQIDAQAB")

Cheers