Fix Linux Server: Ssh Login Error

when i login in ssh i have this lines:

-bash: [: !=: unary operator expected
-bash: [: !=: unary operator expected
-bash: [: !=: unary operator expected
-bash: [: !=: unary operator expected
-bash: [: !=: unary operator expected
-bash: [: !=: unary operator expected
-bash: [: !=: unary operator expected

i don’t know what happened…and i can login in rescue mode

Server: CentOS 5

i am looking for someone who can fix it immediatly.