WordPress madness yesterday. One of my colleagues purchased a Templatic WordPress theme and discovered that all the strings which should read enquiry were instead inquiry (similarly enquire was inquire). Templatic’s support forums are available only to those who have purchased a theme – and Google’s cache. To make the changes (and I recommend changing capitalisations as well) you need to edit the language.php file of the theme.
Do not do a simple blanket search and replace, because the constant names need to remain as INQUIRY. Only change the values.
I’m not sure if these changes will be overwritten if you update the theme.