After your update about x86 & x64, looks like you are not running 32 bit on both. Hence, the data guard set up is not possible.
Following is from Oracle documentation.
Ref:
http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/standby.htm#i72053==========================
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All members of a Data Guard configuration must run an Oracle image that is built for the same platform.
For example, this means a Data Guard configuration with a primary database on a 32-bit Linux on Intel system can have a standby database that is configured on a 32-bit Linux on Intel system. However, a primary database on a 64-bit HP-UX system can also be configured with a standby database on a 32-bit HP-UX system, as long as both servers are running 32-bit images.
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