As far as I know when I've had both installed I couldn't used ActivePerl due to Strawberry Perl already being first installed. You could try installing them in different locations if it's possible and use the full path to it.
For example:
UPDATE: These paths for example only see syphilis post for best answer. 
C:\> C:\StrawberryPerl\Perl\bin\perl.exe perl_script.pl

[download]
or 
C:\> C:\ActivePerl\Perl\bin\perl.exe perl_script.pl

[download]
I've never tried it, but it seems logical, Hope it helps. As I'm sure know there are three distributions of Win32 Perl http://win32.perl.org/wiki/index.php?title=Main_Page#Installing_Perl_on_Windows_for_the_First_Time.3F It all depends on your needs. My only quarrel with Strawberry Perl is it doesn't ship with Win32::* which when changing machines and installing Perl as much as I do can be frustrating as I regularly need it.

In reply to Re: "Strawberry Perl" - can it live together with ActivePerl 5.10.0 Build 1003 (on WinXP)? by binf-jw
in thread "Strawberry Perl" - can it live together with ActivePerl 5.10.0 Build 1003 (on WinXP)? by meorero

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