This has nothing to do with LH. This is purely a UA issue. But, a minor misspelling won't present an issue. The IATA is still met. Do not raise the issue again as all you are doing is creating a problem.

At check-in with LH, your documents will be checked and it is possible that an agent will raise the issue and it may take some time to confirm with a manager that the discrepancy is OK.

For the benefit of others in the future:
1. If you book by phone, have the agent read back every detail, including name spellings. Do not feel rushed.
2. No matter how you book, immediately (but never more than 24 hours later) check every detail of the e-ticket when it arrives. This includes spellings, flights, and the like. Within 24 hours, anything can be corrected because it may be cancelled.