[Rd] R CMD check, NAMESPACE, import: bad error?

[Seth Falcon]

I'm seeing errors with R CMD check that I don't understand when
checking a package that uses a NAMESPACE file with an import
directive.  The imported package is listed in the DESCRIPTION file in
the Imports field.

DESCRIPTION contains:

   Imports: arules

NAMESPACE contains:

   import(arules)

The package builds without warnings and installs and loads just fine.
But check has this to say:

$ R CMD check DNAhelperseth_1.0.tar.gz 
[snip]
* using Version 2.3.0 Under development (unstable) (2006-01-15 r37092) 
* checking for file 'DNAhelperseth/DESCRIPTION' ... OK
[snip]
* checking R files for library.dynam ... OK
* checking S3 generic/method consistency ... WARNING
Error: package/namespace load failed for 'DNAhelperseth'
Call sequence:
2: stop(gettextf("package/namespace load failed for '%s'", libraryPkgName(package)),        call. = FALSE, domain = NA)
1: library(package, lib.loc = lib.loc, character.only = TRUE, verbose = FALSE)
Execution halted
See section 'Generic functions and methods' of the 'Writing R Extensions'
manual.
* checking replacement functions ... WARNING
Error: package/namespace load failed for 'DNAhelperseth'
Call sequence:
2: stop(gettextf("package/namespace load failed for '%s'", libraryPkgName(package)),        call. = FALSE, domain = NA)
1: library(package, lib.loc = lib.loc, character.only = TRUE, verbose = FALSE)
Execution halted
In R, the argument of a replacement function which corresponds to the right
hand side must be named 'value'.
* checking foreign function calls ... WARNING
Error: package/namespace load failed for 'DNAhelperseth'
Call sequence:
2: stop(gettextf("package/namespace load failed for '%s'", libraryPkgName(package)),        call. = FALSE, domain = NA)
1: library(package, lib.loc = lib.loc, character.only = TRUE, verbose = FALSE)
Execution halted
See section 'System and foreign language interfaces' of the 'Writing R
Extensions' manual.
* checking Rd files ... OK
* checking for missing documentation entries ... ERROR
Error: package/namespace load failed for 'DNAhelperseth'