Description of problem:
After the latest update of my system using "yum update" I have got the following error:
# yum update
Loaded plugins: auto-update-debuginfo, langpacks, presto, priorities, refresh-packagekit
Setting up Update Process
Resolving Dependencies
--> Running transaction check
---> Package cyrus-sasl.x86_64 0:2.1.23-17.fc15 will be updated
---> Package cyrus-sasl.x86_64 0:2.1.23-18.fc15 will be an update
---> Package cyrus-sasl-gssapi.x86_64 0:2.1.23-17.fc15 will be updated
---> Package cyrus-sasl-gssapi.x86_64 0:2.1.23-18.fc15 will be an update
---> Package cyrus-sasl-lib.i686 0:2.1.23-17.fc15 will be updated
---> Package cyrus-sasl-lib.x86_64 0:2.1.23-17.fc15 will be updated
---> Package cyrus-sasl-lib.i686 0:2.1.23-18.fc15 will be an update
--> Processing Dependency: libdb-5.1.so for package: cyrus-sasl-lib-2.1.23-18.fc15.i686
---> Package cyrus-sasl-lib.x86_64 0:2.1.23-18.fc15 will be an update
---> Package cyrus-sasl-md5.x86_64 0:2.1.23-17.fc15 will be updated
---> Package cyrus-sasl-md5.x86_64 0:2.1.23-18.fc15 will be an update
---> Package cyrus-sasl-plain.x86_64 0:2.1.23-17.fc15 will be updated
---> Package cyrus-sasl-plain.x86_64 0:2.1.23-18.fc15 will be an update
--> Finished Dependency Resolution
Error: Package: cyrus-sasl-lib-2.1.23-18.fc15.i686 (updates-testing)
           Requires: libdb-5.1.so
 You could try using --skip-broken to work around the problem
 You could try running: rpm -Va --nofiles --nodigest
#

The missing libray libdb-5.1.so is available only for x86_64 platform. There is no package for i686:

# yum whatprovides */libdb-5.1.so
Loaded plugins: auto-update-debuginfo, langpacks, presto, priorities, refresh-packagekit

libdb-5.1.25-2.fc15.x86_64 : The Berkeley DB database library for C
Repo        : fedora
Matched from:
Filename    : /lib64/libdb-5.1.so
Filename    : /usr/lib64/libdb-5.1.so

libdb-5.1.25-2.fc15.x86_64 : The Berkeley DB database library for C
Repo: installed
Matched from:    
Filename:/lib64/libdb-5.1.so
Filename: /usr/lib64/libdb-5.1.so
#

Version-Release number of selected component (if applicable):
* See above

How to reproduce:
Update the Fedora 15 system using "yum update" having installed cyrus-sasl package and enabled Testing Fedora repository