Undefined variable: tmp_modules in nagios_status_page()

We're seeing very frequent errors generated by the code that checks for module and theme update status. The error comes up at line 278 in nagios.module:

$tmp_modules .= ' ' . $projkey . ':' . $tmp_projstatus;

the corresponding error being:

Notice: Undefined variable: tmp_modules in nagios_status_page() (line 279 of sites/all/modules/nagios/nagios.module)

It looks to me like the error is very straightforward and is caused by $tmp_modules not being defined earlier in the code, so that when text is appended to it, we get this problem. It seems to me that the fix is to add an initial assignment, like $tmp_modules = '';, somewhere around line 259. What do you all think? Do other people see this error?

(It can be avoided by turning off the flag to show outdated names, but that's not a very satisfactory fix.)