From the powershell prompt, when I try to run a program and feed it a command line option, powershell ends up mangling the option. Why does this happen? Is there any way to stop it besides enclosing the option in quotes?

For example, from the powershell prompt:

PS Microsoft.PowerShell.Core\FileSystem::\\mach\share> .\myprog.exe -file=input.txt

myprog.exe ends up getting two arguments:

1) -file=input
2) .txt

I need to run it like:

.\myprog.exe "-file=input.txt"

or

.\myprog.exe '-file=input.txt'

to force it to be one argument. No other shell does this.