the !build command only works for some builds, for others it says

syntax is: 'build <job> [now|<delay>[s|m|h]] [<parameterkey>=<value>]*'

I use exactly the name from jenkins view, and there are no blanks or special chars. The name is correct and i have all necesarry right. Btw. Please extend decription which rights (in job and global) are needed to execute !build commands from im.