REMINDER:When recompiling vpopmail, you need to recompile all binaries that link into the vpopmail libraries.  These include QmailAdmin, qmail-smtpd (if you have the chkuser patch applied), Courier-IMAP etc.Upgrading to vpopmail-5.4-------------------------Upgrading to 5.4 from 5.3.x or 5.2.x is straight forward.It should really be a case of following these basic steps  tar xzf vpopmail-5.4.0.tar.gz  cd vpopmail-5.4.0  ./configure --help      # (review the available options)  ./configure [plus your options go here]  # (make sure that you enable the same auth module that you  #  have been previously using.. eg --enable-auth-module=mysql)                   make  make install-stripThis will overwrite your existing vpopmail files with the 5.4 versions.No adjustment to your various qmail run scripts etc should be required.There are only a couple of issues to be aware of :IF USING SMTP AUTH PATCH TO QMAIL-SMTPD  * This release of vpopmail includes fixes for vchkpw that may break    certain SMTP AUTH implementations.  If SMTP AUTH fails after     installing vpopmail 5.4.x, you may need to use the     qmail-smtpd-auth-0.4.2 patch included in the contrib directory.  * If you do switch to the 0.4.2 SMTP AUTH patch, you may need to update    your qmail-smtpd run file (the first parameter to qmail-smtpd should    now be the path to vchkpw and not the hostname).FOR ALL AUTHENICATION MODULES  * Some of the configure settings have changed names. Please    review them using ./configure --help  * Rather than using the --enable-default-domain configure switch,    the default domain now needs to be stored in the file :      ~vpopmail/etc/defaultdomain  * A new limits system has been designed. Once you install vpopmail-5.4,    a file containing the default limits will be created :        ~vpopmail/etc/vlimits.default    You should review the contents of this file to ensure it contains    appropriate values for your site.    Instead of using --enable-defaultquota when configuring vpopmail,    set the default_quota and default_maxmsgcount values in your    ~vpopmail/etc/vlimits.default file.    More information on the limits system is available in README.vlimitsMYSQL SPECIFIC  * Rather than storing the database connection settings in in vmysql.h,    they now need to be stored in       ~vpopmail/etc/vpopmail.mysql    This file will be created apon installation of vpopmail-5.4,    so if you are using MySQL you will need to edit the file so it    contains the correct settings for your database.    Upgrading to vpopmail-5.2-------------------------Everything should be backwardly compatible withthe following exceptions:1. Changes have been made to the way aliased domains   are managed. We have tested backwards compatibility   and can find no problems. 2. Changes have been made to the mysql table formats.   Everything now uses fixed sized columns instead of   varchars for efficency. Your current setup should   work fine.3. Clear text passwords are now enabled by default.   If you are running mysql and you want to use    clear text passwords. basically you will need   to update the table definition. This can be done   on a running system, for example:ALTER TABLE vpopmail ADD COLUMN pw_clear_passwd char(16);Upgrading to vpopmail-5.0 or above----------------------------------Reports from site administrators indicate thatvpopmail can be upgraded cleanly with no problems.They were able to upgrade to vpopmail-5.0 whilethe system remained in production. No need toreboot or restart email. As is always recommended, you should back up thefiles that will be over written. You only needto backup the ~vpopmail/bin directory. No otherfiles are over written. The last thing the development community (me included)is to end up answering alot of emails about problemsupgrading to 5.0 from older versions. So, we triedto make it as easy as possible.The configure options that work for most sites is:./configure ; make ; make install-stripIf you are running a mysql, ldap or anything besidesthe default vpasswd(cdb) module follow the normaldirections in the INSTALL file.Clear text passwords are now enabled by default.If you are running mysql and you want to useclear text passwords. basically you will needto update the table definition. This can be doneon a running system, for example:ALTER TABLE vpopmail ADD COLUMN pw_clear_passwd char(16);If you are using pop authentication before relay,otherwise known as roaming-users add the--enable-roaming-users=y optionIf you are running mysql add:--enable-mysql=y optionIf you think email for jack-test@domain.com should goshould be delivered to jack@domain.com mailbox add:--enable-qmail-ext=y optionIf you are running a site which has many users (more than 10,000)AND you plan on *never* having more than 10 domains on your machineAND you are running mysql/or sql database THEN you may want to considerusing --enable-many-domains=n This option optimizes SQL table normalization. The default --enable-many-domains=y is what most sites need.If you are moving an old mail system over to a new vpopmail 5.0system then might want to useUpgrading to vpopmail-4.9.8 with mysql module:If you were running vpopmail before 4.9.8 and areupgrading to 4.9.8 or newer you might want torun the vcdir program that is in the contribdirectory. See the contrib/vcdir.README file for more details.QuotasPlease read README.quotas for information about the new softquota mechanism.