multiple versions parallel possible?

Hello Group

Is it possible to install (e.g.) 2 differnt version of one rpm-package?
I have krb5-libs-1.3.4-5 installed. Now i want install rb5-libs-1.2.7-14
without to deinstall 1.3.4-5. i can't deinstall the newer version
because some packages depends on this version but i *must* install the
older version for installing e.g. samba 3.0

i try this:

>rpm --rebuild samba3-3.0.14a-21.src.rpm
Installiere samba3-3.0.14a-21.src.rpm
Fehler: Failed build dependencies:
mysql-devel is needed by samba3-3.0.14a-21
postgresql-devel is needed by samba3-3.0.14a-21
openssl-devel is needed by samba3-3.0.14a-21

>yum install mysql-devel postgresql-devel openssl-devel
Gathering header information file(s) from server(s)
Server: Red Hat Linux 9 - i386 - Base
Server: Red Hat Linux 9 - i386 - freshrpms
Server: JPackage 1.6 generic - FREE
Server: JPackage 1.6 generic - NON FREE
Server: kde-redhat.org (kde-stable)
Server: kde-redhat.org (kde-stable-all)
Server: Red Hat Linux 9 - i386 - os
Server: Red Hat Linux 9 - i386 - updates
Finding updated packages
Downloading needed headers
Resolving dependencies
......Unable to satisfy dependencies
Package openssl needs libcom_err.so.3, this is not available.
Package krb5-devel needs krb5-libs = 1.2.7-14, this is not available.
Package krb5-devel needs libcom_err.so.3, this is not available.

>yum install krb5-devel
Gathering header information file(s) from server(s)
Server: Red Hat Linux 9 - i386 - Base
Server: Red Hat Linux 9 - i386 - freshrpms
Server: JPackage 1.6 generic - FREE
Server: JPackage 1.6 generic - NON FREE
Server: kde-redhat.org (kde-stable)
Server: kde-redhat.org (kde-stable-all)
Server: Red Hat Linux 9 - i386 - os
Server: Red Hat Linux 9 - i386 - updates
Finding updated packages
Downloading needed headers
Resolving dependencies
.....Unable to satisfy dependencies
Package krb5-devel needs krb5-libs = 1.2.7-14, this is not available.
Package krb5-devel needs libcom_err.so.3, this is not available.

>rpm -qa krb5-libs
krb5-libs-1.3.4-5

I think my rpm-db is in a very unstable state perheps it was a
mistake to install fedora1 packages in my red hat 9 system *ahhhh*

regards
andreas from germany - sorry for my english