Key legal question
Whether the parties replaced the original wage agreement with a commission-only contract for August-December 1998
Extracted holding
No new contract was concluded; the original employment contract remained in force because the parties never agreed on the commission rate.
Extracted reasoning
A contractual modification requires mutual assent under Art. 1 OR. The employee's commission-based statements showed an attempt to obtain acceptance of 10%, not a concluded agreement. The court could not fill the gap by judicial determination of a wage not agreed by the parties.