The Solaris SPARC Gateway build is only available in a 32-bit build. If you need to log gateway data to a MySQL or MariaDB database you will find that all current releases are only available for 64-bit architectures.
One way to work around this is to download and use the 32-bit MySQL C-Connector. This is available from the C-Connector page: https://dev.mysql.com/downloads/connector/c/
A direct link to the latest version we could find is: https://dev.mysql.com/get/Downloads/Connector-C/mysql-connector-c-6.0.2-solaris10-sparc-32bit.tar.gz
Download and unpack this in a suitable directory. If this is only for use with a single gateway then it can be placed inside the gateway directory. A symlink should be made from the gateway directory to the libmysqlclient_r.so file in the destination and the gateway will pick this up without a restart.