Erro no Archey

Pessoal, instalei Archey(porem sem o ''scrot''), digito archey no terminal e a resposta e essa:

feijo@feijo-laptop:~$ archey
Traceback (most recent call last):
File "/usr/bin/archey", line 304, in <module>
func()
File "/usr/bin/archey", line 288, in disk_display
usedpercent = float(re.sub("[A-Z]", "", used)) / float(re.sub("[A-Z]", "", size)) * 100
ValueError: invalid literal for float(): 4,0
feijo@feijo-laptop:~$

O que pode ser?

Desde já Obrigado.

Abraços!