Hi,
many thanks to all who responded to my post.
Since this is basically for clients, I am (albeit reluctantly) going to convert the graphics to PNGs (which poses another problem for IE, which does not support alpha channels in PNGs, at least IE 6 doesn't).
I converted the font inside the SVG to paths, to avoid problems with the rendering, since this is an uncommon font. I tried to attach links to the text, but removed them, since the links were not indicated (cursor to hand) over the entire area where the text is visible.
Bottom line (for me):
I want to encourage everyone to start using SVGs for web design (wherever feasible), since this opens up so many new possibilities. And regarding the problem of text not being recognized by search engines, I thought about separating the design elements( = SVG) from the content (= text) by putting the text on another layer. In addition, <link rel= ... comes to my mind as /one /means to provide search engines with links they can follow.
Greetings,
Claus