using variables in org-publish-project-alist

[Richard Riley <rileyrgdev@googlemail.com>]

I removed directory names from my projects list thus

,----
| (setq org-publish-project-alist
|       '(
| 	("web-extra"
| 	 :base-directory rgr-source  ;; **********************************
| 	 :publishing-directory rgr-publish
| 	 :base-extension "gif\\|jpg\\|jpeg\\|png\\|css"
| 	 :publishing-function org-publish-attachment
|          :recursive t
| 	 )
| 	("web-org"
| 	 :base-directory rgr-source
| 	 :publishing-directory rgr-publish
| 	 :base-extension "org"
| 	 :publishing-function org-publish-org-to-html
|          :recursive t
| 	 :section-numbers nil
| 	 :style "<link rel=stylesheet
|                      href=\"./style.css\"
|                      type=\"text/css\">"
| 	 :auto-preamble t
| 	 :auto-postamble t
| 	 :preamble (format "<div id='Content'><a href='../'>Back</a> - <a href='%s'>Home</a>" rgr-home)
| 	 :postamble "</div>"
| 	 :author nil
| 	 )
| 	("web"
| 	 :components("web-org" "web-extra")
| 	 )
| 	)
|       )
`----

I included an external file:

,----
| (load-file "~/.emacs.d/.webvars")
`----

where I declares the variables:

,----
| (setq rgr-source "/home/sh/webs/rgr/")
| (setq rgr-publish  "/ssh:rgr.net:/home/sh/webs/rgr/")
| (setq rgr-home "http://rgr.net/default/")
`----

C-h v on "rgr-source" gives

,----
| rgr-source's value is 
| "/home/sh/webs/rgr/"
| 
| Documentation:
| Not documented as a variable.
`----

but when I publish the project or a project file I get this:

,----
| org-publish-get-base-files: Wrong type argument: stringp, rgr-source
`----

I have a niggly feeling its going to be something obvious but what?

thanks for any info,

r.