Juanito built an old version for TC 5 x86, I'm trying to include the same build features:
http://tinycorelinux.net/5.x/x86/tcz/src/mailutils/compile_mailutils
http://tinycorelinux.net/10.x/x86/tcz/mailutils.tcz.info

Old mailutils.tcz.dep:
readline.tcz
libltdl.tcz
gnutls.tcz
tcp_wrappers.tcz

* install extensions: readline-dev libunistring-dev gnutls35-dev tcp_wrappers-dev libltdl libtool-dev compiletc squashfs-tools
* export CFLAGS="-mtune=generic -Os -pipe" CXXFLAGS="-mtune=generic -Os -pipe" LDFLAGS="-Wl,-O1" CC="gcc -flto -fuse-linker-plugin" CXX="g++ -flto -fuse-linker-plugin"
* ./configure --includedir=/usr/local/include --datarootdir=/usr/local/share --exec-prefix=/usr/local --sysconfdir=/etc --disable-static
 - Using "--prefix=/usr/local" modifies /etc and /var paths as well, so avoid that.
*******************************************************************
GNU Mailutils configured with the following settings:

Default mailbox scheme ........ mbox
Use PAM ....................... no
Use -ltdl ..................... yes
Use DBM ....................... no
Use GNU TLS ................... yes
Use GSASL ..................... no
Use GSSAPI .................... no
Use TCP wrappers .............. yes
Pthread support ............... yes
Readline support .............. yes
Libunistring support .......... yes
MySQL support ................. no
PostgreSQL support ............ no
LDAP support .................. no
Radius support ................ no
Support for virtual domains ... yes

IPv6 support .................. yes

Interfaces:

Guile ......................... no
C++ ........................... no
Python ........................ no

Mailbox formats:

IMAP .......................... yes
POP ........................... yes
MH ............................ yes
maildir ....................... yes
dotmail ....................... yes                                                                                                                                  
Mailers:

SMTP .......................... yes
Sendmail ...................... yes

Utilities to build:

Servers ....................... pop3d imap4d comsat mda lmtpd
Clients ....................... putmail frm mail sieve messages readmsg dotlock movemail mimeview decodemail mh

*******************************************************************

* make
* sudo make DESTDIR=/tmp/mailutils install-strip
* split into mailutils.tcz, mailutils-locale.tcz, mailutils-doc.tcz and mailutils-dev.tcz based on files included in earlier x86 extensions.
 - mkdir -p ~/src/mailutils_ext/3.15/mailutils
 - cd ~/src/mailutils_ext/3.15/mailutils
 - for dir in `sed 's/\/[^/]*$//g' ../../mailutils.tcz.list | uniq`; do sudo mkdir -p "$dir"; done
 - for file in `cat ../../mailutils.tcz.list`; do sudo mv /tmp/mailutils/"$file" "$file"; done
 - Note files not found.
 -- Repeat for mailutils-locale and mailutils-dev
 - tree -ap /tmp/mailutils
 - move remailing files to appropriate locations (files not found earlier are a hint)
 - cd /tmp/mailutils
 -find -type f
  - Finds any files missed.
 - cd .. 
 - sudo rm -R mailutils
 - cd ~/src/mailutils_ext/3.15/
 - sudo chown -R root:root *

* In each dir. run "find usr -not -type d > ../program_name.tcz.list".
 - for dir in `find -maxdepth 1 -mindepth 1 -type d`; do cd $dir; find usr -not -type d > ../$dir.tcz.list; cd ..; done

* Make into extensions using mksquashfs. "mksquashfs mailutils mailutils.tcz
* "md5sum mailutils.tcz > mailutils.tcz.md5.txt" etc...
 - for dir in `find -maxdepth 1 -mindepth 1 -type d`; do mksquashfs $dir ${dir#./}.tcz; md5sum ${dir#./}.tcz > ${dir#./}.tcz.md5.txt; done

* Deps:
readline.tcz
libltdl.tcz
gnutls35.tcz
tcp_wrappers.tcz
libunistring.tcz