Is it a web solution? If so then JAWS and NVDA support ARIA attributes which you can add to the html, and both screen readers can work with inline field validation using the correct ARIA roles, states and property attributes.
There is some good advice here on the webaim website which discusses multiple aproaches - inline validation is near the bottom of the article: http://webaim.org/techniques/formvalidation/
Another approach is to display the error messages within the form in
the context of the form control that needs attention. This approach
requires visually distinctive error messages so focus is drawn
immediately to them. The error messages must be associated to their
respective controls (via labeling or perhaps
aria-describedby. It may
be helpful to set focus to the first control that needs attention.
The advantage to the "Inline errors" approach is that the errors appear in context with their respective controls.
The disadvantage is
that the user must visually scan or navigate through the form to
discover the invalid controls and their respective error messages.
This can take some time.