"Inter-process communication" ?
https://www.ibm.com/support/pages/system/files/support/swg/s...
"Interface with COBOL, C, and PL/I applications" !
https://www.ibm.com/common/ssi/rep_ca/2/897/ENUS202-152/ENUS...
"Language-Shifting Objects from Java to Smalltalk"
https://www.yumpu.com/en/document/read/32250538/language-shi...
SOAP ? WSDL ?
"We began selling at the end of 1986, but Smalltalk was not offered out of Xerox itself until mid-1988, said ParcPlace spokeswoman Helene Tannor."
https://techmonitor.ai/techonology/object_oriented_languages...
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Sept 21, 1987 — "A version of the Smalltalk-80 object-oriented development environment … has been announced by Parcplace Systems.
Smalltalk-80 DE version 2.2 is said to provide Unix environments with interprocess communication via sockets and access to Unix C shells. On the Apple Macintosh, it provides access to Desk Accessories and provides the ability to cut and paste between the Smalltalk-80 system and the clipboard."
https://books.google.com/books?id=ldk7z4Q-WWYC&pg=RA4-PA4&lp...
The fact that the only papers thusfar procured were written 15 years later really does not help your point.