NextPrevUpTopContentsIndex Non base-char errors

If your buffer contains a cl:extended-char char then Latin-1 and other encodings which support only cl:base-char are not appropriate. Attempts to save the buffer using such external formats will signal an error ' char is not of type BASE-CHAR'. Set the external format to one which includes char , or delete char from the buffer before saving.

LispWorks Editor User Guide (Macintosh version) - 14 Mar 2008