The "isa_bits" keyword specifies to install 32 or 64 bit software packages, by default 64 bit packages are installed on a sun4u architecture and 32 bit on all others, but when SUNWCreq package cluster is installed the default is to install 32 bit packages for all architectures, the "isa_bits" keyword is used to explicitly install the 64 bit SUNWCreq cluster on sun4u architectures, ie:
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cluster SUNCreq
isa_bits 32
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Only install the 32 bit package.
Regards,
Carlos Almeida,